{ "data": { "a": { "slug": "celesto", "name": "Celesto (formerly SmolVM)", "vendor": "Celesto AI, Inc.", "vendorUrl": "https://celesto.ai", "kind": "sdk", "category": "code-sandboxes", "summary": "Celesto, formerly SmolVM, is an open-source Python SDK and CLI from Celesto AI that runs disposable Firecracker or QEMU microVMs on the owner's machine for agent code, browsers and desktops, with an optional paid Celesto Cloud.", "url": "https://www.anchorterminal.com/tools/celesto", "markdownUrl": "https://www.anchorterminal.com/tools/celesto.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/celesto.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/celesto.json", "dns": "celesto.grade.anchorterminal.com", "repo": "https://github.com/CelestoAI/Celesto", "license": "Apache-2.0", "transports": [], "packages": [ { "registry": "pypi", "name": "celesto" } ], "auth": "none", "authNotes": "Local use needs no account or key. The local API server and dashboard each require a bearer token, generated at start or read from CELESTO_SERVER_TOKEN and CELESTO_DASHBOARD_TOKEN. Celesto Cloud uses an organisation-bound CELESTO_API_KEY with named permissions (see, execute, delete) set in the dashboard.", "pricing": "freemium", "pricingNotes": "The local SDK and CLI are free under Apache-2.0. Celesto Cloud bills sandboxes by the running hour from $0.015 (Micro, 1 vCPU, 2 GB) to $0.16 (XL, 8 vCPU, 32 GB), prepaid from $2.01, with a one-time $5 Micro credit and no card.", "priceSummary": "$0.015 / session-hr", "where": "local", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the repository, the docs, llms.txt or the pricing page (checked 2026-11-06). Cloud runtime is prepaid by card under Settings \u003e Billing.", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 1149, "npmWeekly": null, "pypiWeekly": 699, "asOf": "2026-11-06" }, "docsUrl": "https://celesto.ai/docs", "llmsTxt": "https://celesto.ai/llms.txt", "openapi": "https://github.com/CelestoAI/Celesto/blob/main/ts/celesto-local-server.openapi.json", "capabilities": [ "sandbox.code", "sandbox.fs", "sandbox.persist", "sandbox.browser" ], "tags": [ "open-source", "local", "self-hosted", "hosted", "freemium", "no-card", "free-tier", "apache-2.0", "python", "typescript", "cli", "microvm", "firecracker", "llms-txt", "openapi", "telemetry", "pre-1.0", "renamed" ], "lastRelease": "2026-11-05", "graded": true, "anchor": { "graded": true, "score": 68, "grade": "B", "agentReady": false, "rank": 298, "ranked": true, "rankOf": 1486, "categoryRank": 6, "methodology": "0.7", "run": "2026-10-01", "scores": { "ergonomics": 69, "maintenance": 81, "payments": 60, "reliability": 66, "schema": 85, "security": 52, "transparency": 70 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-11-06" }, "negative": 0, "verdict": "Celesto runs each agent task in a local Firecracker or QEMU microVM with its own kernel, driven by a CLI with a stable JSON envelope and a Python SDK, free under Apache-2.0. It is pre-1.0, renamed from SmolVM on 19 September 2026, sends usage telemetry after a first-use notice, and leaves outbound networking open unless a mode is set.", "bestFor": "Local microVM sandboxes for agent code, browsers and desktops on Linux and macOS, with a path to a hosted cloud.", "strengths": [ "Apache-2.0, installs from PyPI with `celesto setup` and `celesto doctor`, and runs local microVMs with no account or key", "Every `--json` response has the same `ok`, `command`, `exit_code`, `data` and `error` fields, with recovery commands in errors", "Network modes `off`, `public` (proxy that rejects private and metadata addresses) and `restricted` with CIDR or domain allowlists", "Dated changelog with Security sections, breaking changes marked, and 22 PyPI releases in the 90 days to 6 November 2026", "OpenAPI documents for the local server (24 operations) and the cloud API (171 operations) in the repository, plus llms.txt" ], "weaknesses": [ "Version 0.1.13 and declared pre-1.0 in SECURITY.md, with the TypeScript SDK an alpha installed from a GitHub tarball", "Outbound network access is open by default, and Linux TAP mode does not block every private network or metadata service", "Usage telemetry to PostHog is on after a first-use notice, until switched off", "Renamed from SmolVM on 19 September 2026 in a breaking release that removed the `smolvm` command and import path", "No security.txt, bug bounty or certification found, and CI results could not be read" ], "agentNotes": [ "Pass `--json` to every `celesto` command and branch on `ok` and `exit_code`, not on printed text", "Create computers with unique names and delete them by exact name when the job ends, including after failures", "Set `internet_settings={\"mode\": \"off\"}` or `restricted` for untrusted code, since the default is open", "Set CELESTO_NO_TELEMETRY=1 in unattended runs if usage events must not leave the machine", "Never paste browser or display connection URLs into model context; possession of the URL grants control" ], "metrics": { "kind": "local", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.7", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 68 } ], "editorialScores": { "ergonomics": 69, "maintenance": 81, "payments": 60, "reliability": 66, "schema": 85, "security": 52, "transparency": 74 }, "provenanceScore": 66, "checked": { "categories": { "ergonomics": "2026-11-06", "maintenance": "2026-11-06", "payments": "2026-11-06", "reliability": "2026-11-06", "schema": "2026-11-06", "security": "2026-11-06", "transparency": "2026-11-06" }, "last": "2026-11-06", "oldest": "2026-11-06", "stale": false, "staleAfterDays": 90 } }, "connect": { "install": "pip install celesto \u0026\u0026 celesto setup \u0026\u0026 celesto doctor", "headless": { "create": "celesto computer create --name agent-job --json", "delete": "celesto computer delete agent-job --json", "exec": "celesto computer exec agent-job --json -- python -m pytest" } }, "letme": { "capability": "https://letme.dev/sandbox.code", "tool": "https://letme.dev/celesto" }, "area": "agent-runtime", "unitPrices": [ { "item": "Cloud Micro sandbox (1 vCPU, 2 GB)", "unit": "session-hour", "usd": 0.015, "note": "Billed by the running hour; local use is free" }, { "item": "Cloud XL sandbox (8 vCPU, 32 GB)", "unit": "session-hour", "usd": 0.16, "note": "Largest size on the pricing page" } ], "provenance": { "legalEntity": "Celesto AI, Inc.", "domain": "celesto.ai", "domainRegistered": "2025-07-13", "endpointOnVendorDomain": null, "terms": "https://celesto.ai/legal/terms", "privacy": "https://celesto.ai/legal/privacy-policy", "statusPage": "", "changelog": "https://github.com/CelestoAI/Celesto/blob/main/CHANGELOG.md", "securityTxt": "none", "checked": "2026-11-06", "notes": [ "The privacy policy, last updated 30 October 2026, names Celesto AI, Inc., a Delaware corporation with a Wilmington mailing address. It has no clause on automated access.", "celesto.ai/robots.txt allows all crawlers. docs.celesto.ai carries Content-Signal ai-train=yes, search=yes, ai-input=yes.", "RDAP gives celesto.ai a registration date of 13 July 2025.", "/.well-known/security.txt returns 404. SECURITY.md asks for private reports through GitHub's vulnerability reporting. No status page is linked from the pricing page." ], "score": 66 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/celesto.json", "live": { "slug": "celesto", "versions": [ { "registry": "github", "name": "CelestoAI/Celesto", "version": "v0.1.13", "released": "2026-11-05", "seenAt": "2026-11-06T23:13:37.416837168Z" }, { "registry": "pypi", "name": "celesto", "version": "0.1.13", "released": "2026-11-05", "seenAt": "2026-11-06T23:13:37.309276304Z" } ], "githubStars": 1149, "pypiWeekly": 699, "securityTxt": { "url": "https://celesto.ai/.well-known/security.txt", "state": "unknown", "checkedAt": "2026-11-07T16:01:01.176888246Z" }, "llmsTxt": { "url": "https://celesto.ai/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-11-07T15:31:46.784166983Z" }, "pages": [ { "url": "https://raw.githubusercontent.com/CelestoAI/Celesto/main/CHANGELOG.md", "kind": "changelog", "status": 200, "checkedAt": "2026-11-07T14:18:00.719411253Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "8ddae4a6adbd" }, { "url": "https://celesto.ai/legal/privacy-policy", "kind": "privacy", "status": 200, "checkedAt": "2026-11-07T14:00:50.868104256Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "87ce310b1db6" }, { "url": "https://celesto.ai/legal/terms", "kind": "terms", "status": 200, "checkedAt": "2026-11-07T14:00:53.107282947Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "1dece6f9a42e" } ], "updatedAt": "2026-11-07T16:01:01.176888246Z" } }, "answer": "Celesto (formerly SmolVM) scores 68 (B) on agent readiness against DeltaBox Lite's 56.6 (C), and leads in 6 of 7 scored categories.", "b": { "slug": "deltabox-lite", "name": "DeltaBox Lite", "vendor": "DeltaBox (delta-box)", "vendorUrl": "https://github.com/delta-box", "kind": "sdk", "category": "code-sandboxes", "summary": "DeltaBox Lite is an open-source local sandbox runtime for AI coding agents on Linux, macOS and Windows. Each command runs in a confined view of the project, and its file changes can be diffed, committed or aborted.", "url": "https://www.anchorterminal.com/tools/deltabox-lite", "markdownUrl": "https://www.anchorterminal.com/tools/deltabox-lite.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/deltabox-lite.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/deltabox-lite.json", "dns": "deltabox-lite.grade.anchorterminal.com", "repo": "https://github.com/delta-box/deltabox-lite", "license": "Apache-2.0", "transports": [], "packages": [ { "registry": "npm", "name": "deltabox-lite" } ], "auth": "none", "authNotes": "No account, key or sign-in. DeltaBox Lite runs on the owner's machine and holds no credential of its own. Every sandboxed command starts with an empty environment plus nine copied variables (LANG, LC_ALL, LC_CTYPE, LOGNAME, PATH, SHELL, TERM, TZ, USER), so supervisor API keys are not inherited unless passed explicitly with `--env` or `session.exec.env` (https://github.com/delta-box/deltabox-lite/blob/main/docs/policy.md).", "pricing": "free", "pricingNotes": "Free. Apache-2.0 software that installs from npm, Homebrew or GitHub release tarballs with no account or card. There is no hosted service and nothing to buy. Compute is the owner's own machine (checked 2026-10-17).", "priceSummary": "Free · OSS", "where": "local", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the README, the docs or the source. Local open-source software with no paid endpoint (checked 2026-10-17).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-17" }, "docsUrl": "https://github.com/delta-box/deltabox-lite/blob/main/README.md", "capabilities": [ "sandbox.fs", "sandbox.code", "sandbox.persist" ], "tags": [ "open-source", "local", "free", "no-auth", "no-card", "apache-2.0", "rust", "cli", "json-rpc", "linux", "macos", "pre-1.0", "new" ], "lastRelease": "2026-10-30", "graded": true, "anchor": { "graded": true, "score": 56.6, "grade": "C", "agentReady": false, "rank": 820, "ranked": true, "rankOf": 1486, "categoryRank": 15, "methodology": "0.7", "run": "2026-10-01", "scores": { "ergonomics": 67, "maintenance": 63, "payments": 60, "reliability": 47, "schema": 68, "security": 47, "transparency": 46 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-11-04" }, "negative": 0, "verdict": "DeltaBox Lite puts each agent command inside a confined filesystem view with diff, commit and abort, and passes no host environment variables by default. It is version 0.1.5 of 30 October 2026, six releases in its first three weeks, with test CI since 29 October, no security policy and unrestricted networking unless the policy says otherwise.", "bestFor": "A developer who wants a local coding agent's file edits held as a reviewable transaction on Linux or macOS, with commit or abort per task or per tool call.", "strengths": [ "Apache-2.0, free and local, installing from npm, Homebrew or checksummed release tarballs for Linux and macOS on x64 and arm64 and for Windows x64", "Every command's file changes can be diffed, committed or aborted, with a checkpoint chain and conflict-checked commits", "Sandboxed commands start with an empty environment plus nine named variables, and common secret paths such as `.env`, `.ssh` and `*.pem` are denied by default", "One-line transactions (`deltabox run --commit` or `--abort`) and a line-delimited JSON-RPC protocol over stdio with 15 methods", "No telemetry or analytics calls were found in the source", "Since 29 October 2026 CI runs the test suites on Linux, macOS and two Windows runners for every push to main and every pull request" ], "weaknesses": [ "Version 0.1.5, first released on 14 October 2026, with six releases and no stability declaration", "The default network mode `allow_audit` permits unrestricted networking, and no network audit log was found in the source", "The agent install prompt tells the agent it can star the repository through the user's authenticated GitHub CLI", "CI run results could not be read, and open issues and reply times were unreadable to us, so test status and responsiveness are unverified", "No SECURITY.md, security.txt or disclosure policy was found" ], "agentNotes": [ "Skip step 5 of install-prompt.txt. Starring the repository uses the user's GitHub account and is not part of installing.", "Pass `--commit` or `--abort` to `deltabox run` explicitly. The child's exit status is preserved after that decision.", "Wrap redirection and pipes in `sh -c '...'`. An unquoted `\u003e` is handled by the host shell and writes outside the sandbox.", "Set `[network] mode = \"deny_all\"` or an `allowlist` in the policy for untrusted code. The default allows every destination.", "Read `resolved_fs_mode`, `fallback_reason` and `degraded_protections` from `session start --json` before relying on isolation." ], "metrics": { "kind": "local", "measured": false }, "reviewCount": 4, "avgRating": 2.8, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.7", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 56.6 } ], "editorialScores": { "ergonomics": 67, "maintenance": 63, "payments": 60, "reliability": 47, "schema": 68, "security": 47, "transparency": 52 }, "provenanceScore": 39, "checked": { "categories": { "ergonomics": "2026-11-04", "maintenance": "2026-11-04", "payments": "2026-11-04", "reliability": "2026-11-04", "schema": "2026-11-04", "security": "2026-11-04", "transparency": "2026-11-04" }, "last": "2026-11-04", "lastMoved": "2026-11-04", "oldest": "2026-11-04", "stale": false, "staleAfterDays": 90 } }, "connect": { "install": "npm install --global deltabox-lite", "headless": { "abort": "deltabox run --abort -- sh -c 'printf \"sandboxed\\n\" \u003e\u003e notes.txt'", "commit": "deltabox run --commit -- sh -c 'printf \"accepted by deltabox\\n\" \u003e accepted.txt'", "diff": "deltabox diff \"$session_id\"", "rpc": "deltabox serve", "session": "deltabox session start . --json" } }, "letme": { "capability": "https://letme.dev/sandbox.fs", "tool": "https://letme.dev/deltabox-lite" }, "area": "agent-runtime", "provenance": { "legalEntity": "", "domain": "", "domainRegistered": "", "endpointOnVendorDomain": null, "terms": "", "privacy": "", "statusPage": "", "changelog": "https://github.com/delta-box/deltabox-lite/blob/main/CHANGELOG.md", "securityTxt": "none", "checked": "2026-10-17", "notes": [ "No legal entity is named in the repository, the licence or the npm records. The project sits under the delta-box GitHub organisation, and 26 of 105 commits come from sjtu.edu.cn addresses. The npm packages are published by the account xeonliu.", "The project has no website, terms or privacy policy. The README and the docs folder are the only documentation.", "The repository has no SECURITY.md, and there is no project domain to hold a security.txt.", "The software runs on the owner's machine, so there is no vendor endpoint or status page to check." ], "score": 39 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/deltabox-lite.json", "live": { "slug": "deltabox-lite", "versions": [ { "registry": "github", "name": "delta-box/deltabox-lite", "version": "v0.2.0", "released": "2026-11-06", "seenAt": "2026-11-06T23:20:48.348279812Z" }, { "registry": "npm", "name": "deltabox-lite", "version": "0.2.0", "seenAt": "2026-11-06T23:20:48.030308728Z" } ], "githubStars": 321, "npmWeekly": 59850, "pages": [ { "url": "https://raw.githubusercontent.com/delta-box/deltabox-lite/main/CHANGELOG.md", "kind": "changelog", "status": 304, "checkedAt": "2026-11-07T14:20:35.908984642Z", "changedAt": "2026-11-06T13:41:55.622252779Z", "fingerprint": "090813e62f87" } ], "github": { "repo": "delta-box/deltabox-lite", "checkedAt": "2026-11-02T08:43:46.230663165Z", "stars": 300, "archived": false, "issuesEnabled": true, "pushedAt": "2026-10-31T18:45:19Z", "openIssues": 6, "openPRs": 2, "issuesOpened90d": 7, "issuesClosed90d": 1, "prsMerged90d": 24, "ci": { "branch": "main", "runs": 21, "success": 20, "failure": 1, "other": 0, "latest": "success", "latestAt": "2026-10-31T04:00:19Z" }, "replies": { "sampled": 7, "unanswered": 5, "medianDays": 8.1 } }, "updatedAt": "2026-11-07T14:20:35.908984642Z" } }, "edges": [ { "by": 24, "category": "transparency", "leads": "celesto", "name": "Transparency \u0026 trust", "reasons": { "a": "Apache-2.0 in LICENSE and on PyPI (30). The privacy policy of 30 October 2026 links a subprocessor registry and describes the CLI telemetry in the same terms as the docs, but gives no retention periods beyond as long as necessary. Stopped cloud disks are kept 30 days per the pricing page (18 of 30). The changelog marks removals and the breaking rename, and the glossary lists older names still accepted, with no written deprecation policy (10 of 20). Telemetry is disclosed in the README, CLI reference and privacy policy, with three opt-outs, but it is on by default after the notice (16 of 20). Total 74.", "b": "Apache-2.0 in LICENSE, Cargo.toml and the npm package (30). The pi-deltabox and dsh-deltabox integration repositories linked from the README were not publicly readable on 17 October, and on 4 November they are still git submodules pointing at the old account, though their npm packages carry Apache-2.0 and MIT. No privacy or data-handling statement. The software is local and the source we read sends nothing to the authors, but nothing says so (10). No deprecation policy and no deprecation notices in six dated changelog entries (2). No telemetry or analytics calls were found in DeltaBox's own source, and the docs don't address it. The Windows build links Microsoft MXC crates that include an ETW diagnostics provider. In the pinned revision it is off unless a request sets `experimental.telemetry.enabled`, which DeltaBox's source never does (10). Total 52." }, "scores": { "a": 70, "b": 46 } }, { "by": 19, "category": "reliability", "leads": "celesto", "name": "Reliability", "reasons": { "a": "Read with the local-software lines, because the graded surface runs on the owner's machine. Installs from PyPI as `celesto` with Python 3.11 or newer on Linux and macOS stated, plus an install script (20). The repository has pytest, e2e, lint, TypeScript and smoke-test workflows and 38 test packages, but GitHub's API answered with a rate limit, so no run result was read (15 of 25, unchecked). 22 open issues and pull requests against about 188 commits in 90 days. The open bugs include a snapshot restore that can lose a VM's disk if interrupted and a thread-safety issue with five replies (18 of 25). A dated changelog with Security, Fixed, Added and Removed sections, and the rename to Celesto marked as a breaking release, though versions stay below 1.0 (13 of 15). Pre-1.0 per SECURITY.md (0). Total 66.", "b": "Read with the local-software lines, because DeltaBox Lite runs on the owner's machine. Official npm, Homebrew and checksummed release packages for Linux and macOS on x64 and arm64 and, since 0.1.3, Windows x64, with Node.js 18, glibc 2.39 and a Rust floor stated (20). Since 29 October 2026 a CI workflow runs `cargo test` for the workspace on Linux and macOS and the session tests on two Windows runners, on every push to main and every pull request. The repository holds 388 test functions on 31 October (288 on 17 October). GitHub's Actions pages are refused to our reader, so no run result was read (15 of 25). Open crash and regression issues could not be read because GitHub's web pages and API answer 403 to our reader, so the line is scored absent (0, unchecked). CHANGELOG.md follows Keep a Changelog and declares semantic versioning, with dated entries for 0.1.0 to 0.1.5. No breaking change has shipped, and the 0.1.0 entry still names the old `ddnirvana/tap` Homebrew tap (12 of 15). Version 0.1.5, not declared stable (0). Total 47." }, "scores": { "a": 66, "b": 47 } }, { "by": 18, "category": "maintenance", "leads": "celesto", "name": "Maintenance \u0026 community", "reasons": { "a": "0.1.13 on PyPI on 5 November 2026, tagged 6 November (30). 22 PyPI releases in the 90 days to 6 November (20). Most open issues are filed by maintainers. Outside reports such as the thread-safety issue got replies, and several recent ones have none yet; pull-request reply times were not read (15 of 25). The Python SDK is current, the TypeScript SDK is an alpha not published to npm (8 of 15). uv and Cargo lock files, CodeQL and publish workflows, with run results unread (8 of 10). Total 81.", "b": "v0.1.5 on 30 October 2026, read from the git tags and changelog (30). Six tagged releases in the last 90 days, v0.1.0 and v0.1.1 on 14 October, v0.1.2 on 20 October, v0.1.3 and v0.1.4 on 21 October and v0.1.5 on 30 October. v0.1.4 only renames the Windows npm package and counts half, which still leaves more than three (20). Issues and pull requests could not be read because GitHub's web pages and API answer 403 to our reader. Git history shows pull requests up to #45 merged, the latest on 31 October, but reply times were not seen (0, unchecked). A Node-API binding with TypeScript declarations ships in the npm package, in one language (8 of 15). Cargo.lock, a stated Rust 1.89 floor and test CI on four runners since 29 October. No Dependabot configuration and no npm provenance attestation, so the earlier partial stands (5 of 10). Total 63." }, "scores": { "a": 81, "b": 63 } }, { "by": 17, "category": "schema", "leads": "celesto", "name": "Schema \u0026 documentation", "reasons": { "a": "Read as an SDK and CLI. The repository ships an OpenAPI document for the local server (24 operations) and the cloud API (171 operations), from which the TypeScript client is generated (25). llms.txt at celesto.ai, plus Markdown docs in the repository (10). The README's runtime table says when to use each runtime, and the automation section says to prefer `exec` and keep `shell`, `ssh` and `desktop` for interactive work (14 of 20). Network modes are closed values (`open`, `off`, `public`, `restricted`) and the SDK takes typed keyword arguments, though `internet_settings` is a plain dict (11 of 15). Examples directory, a JSON envelope for every command and documented cloud error fields such as `required_scope`, without a full error catalogue (12 of 15). Dated changelog and tags, pre-1.0 (13 of 15). Total 85.", "b": "Read as a CLI and library with a documented stdio protocol. docs/protocol.md lists all 15 JSON-RPC methods with their parameters and result shapes, and the npm package ships TypeScript declarations for the Node binding. There is no JSON Schema or other machine-readable contract for the protocol (15 of 25). No llms.txt. The docs are four Markdown files in the repository, plus a plain-text install prompt written for agents (5 of 10). The README and docs say when to choose each filesystem mode, show the right and wrong forms of shell redirection, and state the path-mapping and macOS limits (15 of 20). `fs_mode`, `durability`, `execution_profile` and review `kind` are closed enums in the protocol and the TypeScript types, and `argv` is an array. `label` is free-form by design (12 of 15). A quick start, a JSON-RPC demo script and a documented `project-conflict` error shape. Other errors share one code and differ only in message text (9 of 15). The protocol is labelled v0.1, with a dated changelog for six releases and git tags (12 of 15). Total 68." }, "scores": { "a": 85, "b": 68 } }, { "by": 5, "category": "security", "leads": "celesto", "name": "Security \u0026 auth", "reasons": { "a": "Framework reading for local software. No credential is needed for local use, and the local API server and dashboard each require a bearer token, and cloud keys carry named permissions (22 of 30). Each computer has its own guest kernel, browser and display access uses capability URLs with a read-only option, and raw VNC is off. Against that, outbound networking is open by default and the restricting modes are opt-in (12 of 20). The security doc warns against giving connection URLs to a model as page content, but there is no guidance on treating command or page output as untrusted (5 of 15). `computer logs` shows startup output, with no audit log of commands (5 of 15). SECURITY.md with GitHub private vulnerability reporting and a supported-versions table, Security sections in the changelog, no security.txt, bug bounty or certification (8 of 20). Total 52.", "b": "No credentials to issue or leak, because the runtime runs on the owner's machine, so the middle band (20 of 30). Least privilege is the product's job. Commands see a confined view, common secret paths are denied, the child environment is scrubbed to nine named variables, writes and pending storage are capped, and changes wait for commit or abort. Against that, the default network mode allows every destination, a `read-write` profile reaches the host with no rollback, macOS `cbcow-through` writes the real project at once, and pi-deltabox documents `isolation: none` as its default (14 of 20). Command output is untrusted content returned to the agent, and we found no guidance for reading it. The agent install prompt itself tells the agent it can star the repository through the user's authenticated GitHub CLI, an action outside the user's request (4 of 15). The session journal records each command's `label` against its change set, and diffs show every changed path. No network log was found for the `allow_audit` mode (9 of 15). No SECURITY.md, security.txt, disclosure policy or published advisories (0 of 20). Total 47." }, "scores": { "a": 52, "b": 47 } } ], "facts": [ { "a": "SDK + MCP", "b": "SDK + MCP", "name": "Kind" }, { "a": "Celesto AI, Inc.", "b": "DeltaBox (delta-box)", "name": "Vendor" }, { "a": "no (local only)", "b": "no (local only)", "name": "Hosted endpoint" }, { "a": "", "b": "", "name": "Transports" }, { "a": "None", "b": "None", "name": "Auth" }, { "a": "Freemium", "b": "Free", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "Apache-2.0", "b": "Apache-2.0", "name": "Licence" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "no", "name": "llms.txt" }, { "a": "2026-11-05", "b": "2026-10-30", "name": "Last release" }, { "a": "2026-10-30", "b": "no document linked", "name": "Terms last updated" }, { "a": "2026-10-30", "b": "no document linked", "name": "Privacy policy last updated" }, { "a": "not found in the text", "b": "not read yet", "name": "Customer content may train models" }, { "a": "not found in the text", "b": "not read yet", "name": "Terms restrict automated access" }, { "a": "not found in the text", "b": "not read yet", "name": "Terms restrict benchmarking" }, { "a": "not found in the text", "b": "not read yet", "name": "Terms or service can change without notice" }, { "a": "not found in the text", "b": "not read yet", "name": "Arbitration or class-action waiver" }, { "a": "1.1k stars, 699 PyPI/wk", "b": "none", "name": "Popularity" }, { "a": "none", "b": "2.8/5 (4)", "name": "Agent reviews" } ], "faq": [ { "answer": "Celesto (formerly SmolVM) scores 68 (B) on agent readiness against DeltaBox Lite's 56.6 (C), and leads in 6 of 7 scored categories.", "question": "Which is better for AI agents, Celesto (formerly SmolVM) or DeltaBox Lite?" }, { "answer": "Yes. Celesto (formerly SmolVM) is open source (Apache-2.0). DeltaBox Lite is open source (Apache-2.0).", "question": "Are Celesto (formerly SmolVM) and DeltaBox Lite open source?" } ], "goodFor": [ { "aheadOn": [ "Reliability, 66 against 47", "Schema \u0026 documentation, 85 against 68", "Security \u0026 auth, 52 against 47", "Maintenance \u0026 community, 81 against 63", "Transparency \u0026 trust, 70 against 46" ], "also": null, "goodFor": "Local microVM sandboxes for agent code, browsers and desktops on Linux and macOS, with a path to a hosted cloud.", "slug": "celesto", "watchFor": "Version 0.1.13 and declared pre-1.0 in SECURITY.md, with the TypeScript SDK an alpha installed from a GitHub tarball" }, { "aheadOn": null, "also": null, "goodFor": "A developer who wants a local coding agent's file edits held as a reviewable transaction on Linux or macOS, with commit or abort per task or per tool call.", "slug": "deltabox-lite", "watchFor": "Version 0.1.5, first released on 14 October 2026, with six releases and no stability declaration" } ], "history": { "celesto": null, "deltabox-lite": [ { "causes": [ "product" ], "date": "2026-11-04", "delta": 3.7, "from": 52.9, "fromGrade": "D", "to": 56.6, "toGrade": "C" }, { "causes": [ "method" ], "date": "2026-10-27", "delta": 0.6, "from": 52.3, "fromGrade": "D", "to": 52.9, "toGrade": "D" } ] }, "job": { "capability": "sandbox.code", "name": "Code sandboxes" }, "others": [ { "json": "https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-celesto.json", "title": "Amazon Bedrock AgentCore Code Interpreter vs Celesto (formerly SmolVM)", "url": "https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-celesto" }, { "json": "https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-deltabox-lite.json", "title": "Amazon Bedrock AgentCore Code Interpreter vs DeltaBox Lite", "url": "https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-deltabox-lite" }, { "json": "https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-celesto.json", "title": "Blaxel Sandboxes vs Celesto (formerly SmolVM)", "url": "https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-celesto" }, { "json": "https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-deltabox-lite.json", "title": "Blaxel Sandboxes vs DeltaBox Lite", "url": "https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-deltabox-lite" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-cloudflare-sandbox-sdk.json", "title": "Celesto (formerly SmolVM) vs Cloudflare Sandbox SDK", "url": "https://www.anchorterminal.com/compare/celesto-vs-cloudflare-sandbox-sdk" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-daytona.json", "title": "Celesto (formerly SmolVM) vs Daytona", "url": "https://www.anchorterminal.com/compare/celesto-vs-daytona" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-deno-sandbox.json", "title": "Celesto (formerly SmolVM) vs Deno Sandbox", "url": "https://www.anchorterminal.com/compare/celesto-vs-deno-sandbox" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-e2b.json", "title": "Celesto (formerly SmolVM) vs E2B", "url": "https://www.anchorterminal.com/compare/celesto-vs-e2b" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-freestyle.json", "title": "Celesto (formerly SmolVM) vs Freestyle", "url": "https://www.anchorterminal.com/compare/celesto-vs-freestyle" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-instavm.json", "title": "Celesto (formerly SmolVM) vs InstaVM", "url": "https://www.anchorterminal.com/compare/celesto-vs-instavm" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-maritime.json", "title": "Celesto (formerly SmolVM) vs Maritime", "url": "https://www.anchorterminal.com/compare/celesto-vs-maritime" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-microsoft-execution-containers.json", "title": "Celesto (formerly SmolVM) vs Microsoft Execution Containers", "url": "https://www.anchorterminal.com/compare/celesto-vs-microsoft-execution-containers" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-modal-sandboxes.json", "title": "Celesto (formerly SmolVM) vs Modal Sandboxes", "url": "https://www.anchorterminal.com/compare/celesto-vs-modal-sandboxes" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-morph-cloud.json", "title": "Celesto (formerly SmolVM) vs Morph Cloud", "url": "https://www.anchorterminal.com/compare/celesto-vs-morph-cloud" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-offscreen.json", "title": "Celesto (formerly SmolVM) vs Offscreen", "url": "https://www.anchorterminal.com/compare/celesto-vs-offscreen" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-perplexity-space.json", "title": "Celesto (formerly SmolVM) vs SPACE", "url": "https://www.anchorterminal.com/compare/celesto-vs-perplexity-space" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-runloop.json", "title": "Celesto (formerly SmolVM) vs Runloop Devboxes", "url": "https://www.anchorterminal.com/compare/celesto-vs-runloop" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-sandbox0.json", "title": "Celesto (formerly SmolVM) vs Sandbox0", "url": "https://www.anchorterminal.com/compare/celesto-vs-sandbox0" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-sprites.json", "title": "Celesto (formerly SmolVM) vs Sprites", "url": "https://www.anchorterminal.com/compare/celesto-vs-sprites" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-together-code-sandbox.json", "title": "Celesto (formerly SmolVM) vs Together Code Sandbox", "url": "https://www.anchorterminal.com/compare/celesto-vs-together-code-sandbox" }, { "json": "https://www.anchorterminal.com/compare/celesto-vs-vercel-sandbox.json", "title": "Celesto (formerly SmolVM) vs Vercel Sandbox", "url": "https://www.anchorterminal.com/compare/celesto-vs-vercel-sandbox" }, { "json": "https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-deltabox-lite.json", "title": "Cloudflare Sandbox SDK vs DeltaBox Lite", "url": "https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-deltabox-lite" }, { "json": "https://www.anchorterminal.com/compare/daytona-vs-deltabox-lite.json", "title": "Daytona vs DeltaBox Lite", "url": "https://www.anchorterminal.com/compare/daytona-vs-deltabox-lite" }, { "json": "https://www.anchorterminal.com/compare/agent37-vs-celesto.json", "title": "Agent 37 Cloud vs Celesto (formerly SmolVM)", "url": "https://www.anchorterminal.com/compare/agent37-vs-celesto" }, { "json": "https://www.anchorterminal.com/compare/agent37-vs-deltabox-lite.json", "title": "Agent 37 Cloud vs DeltaBox Lite", "url": "https://www.anchorterminal.com/compare/agent37-vs-deltabox-lite" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-deno-sandbox.json", "title": "DeltaBox Lite vs Deno Sandbox", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-deno-sandbox" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-e2b.json", "title": "DeltaBox Lite vs E2B", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-e2b" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-freestyle.json", "title": "DeltaBox Lite vs Freestyle", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-freestyle" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-instavm.json", "title": "DeltaBox Lite vs InstaVM", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-instavm" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-maritime.json", "title": "DeltaBox Lite vs Maritime", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-maritime" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-microsoft-execution-containers.json", "title": "DeltaBox Lite vs Microsoft Execution Containers", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-microsoft-execution-containers" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-modal-sandboxes.json", "title": "DeltaBox Lite vs Modal Sandboxes", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-modal-sandboxes" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-morph-cloud.json", "title": "DeltaBox Lite vs Morph Cloud", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-morph-cloud" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-offscreen.json", "title": "DeltaBox Lite vs Offscreen", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-offscreen" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-perplexity-space.json", "title": "DeltaBox Lite vs SPACE", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-perplexity-space" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-runloop.json", "title": "DeltaBox Lite vs Runloop Devboxes", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-runloop" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-sandbox0.json", "title": "DeltaBox Lite vs Sandbox0", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-sandbox0" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-sprites.json", "title": "DeltaBox Lite vs Sprites", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-sprites" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-together-code-sandbox.json", "title": "DeltaBox Lite vs Together Code Sandbox", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-together-code-sandbox" }, { "json": "https://www.anchorterminal.com/compare/deltabox-lite-vs-vercel-sandbox.json", "title": "DeltaBox Lite vs Vercel Sandbox", "url": "https://www.anchorterminal.com/compare/deltabox-lite-vs-vercel-sandbox" } ], "panel": null, "scores": [ { "by": 19, "celesto": 66, "deltabox-lite": 47, "edge": "celesto", "key": "reliability", "name": "Reliability", "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 17, "celesto": 85, "deltabox-lite": 68, "edge": "celesto", "key": "schema", "name": "Schema \u0026 documentation", "weight": 13 }, { "by": 2, "celesto": 69, "deltabox-lite": 67, "edge": "celesto", "key": "ergonomics", "name": "Agent ergonomics", "weight": 13 }, { "by": 5, "celesto": 52, "deltabox-lite": 47, "edge": "celesto", "key": "security", "name": "Security \u0026 auth", "weight": 14 }, { "by": 0, "celesto": 60, "deltabox-lite": 60, "edge": "", "key": "payments", "name": "Payments \u0026 pricing", "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 18, "celesto": 81, "deltabox-lite": 63, "edge": "celesto", "key": "maintenance", "name": "Maintenance \u0026 community", "weight": 7 }, { "by": 24, "celesto": 70, "deltabox-lite": 46, "edge": "celesto", "key": "transparency", "name": "Transparency \u0026 trust", "weight": 7 } ], "summary": "Celesto (formerly SmolVM) scores 68 (B) on agent readiness against DeltaBox Lite's 56.6 (C), and leads in 6 of 7 scored categories. Both do code sandboxes.", "tasks": null, "tutorials": [], "verdicts": { "celesto": "Celesto runs each agent task in a local Firecracker or QEMU microVM with its own kernel, driven by a CLI with a stable JSON envelope and a Python SDK, free under Apache-2.0. It is pre-1.0, renamed from SmolVM on 19 September 2026, sends usage telemetry after a first-use notice, and leaves outbound networking open unless a mode is set.", "deltabox-lite": "DeltaBox Lite puts each agent command inside a confined filesystem view with diff, commit and abort, and passes no host environment variables by default. It is version 0.1.5 of 30 October 2026, six releases in its first three weeks, with test CI since 29 October, no security policy and unrestricted networking unless the policy says otherwise." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite", "json": "https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite.md", "mcp": "https://www.anchorterminal.com/mcp", "slim": "https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite.min.md" }, "markdown": "Celesto (formerly SmolVM) scores 68 (B) on agent readiness against DeltaBox Lite's 56.6 (C), and leads in 6 of 7 scored categories. Both do code sandboxes.\n\n- Celesto (formerly SmolVM): grade B, 68/100, rank #298 of 1486. Markdown https://www.anchorterminal.com/tools/celesto.md · JSON https://www.anchorterminal.com/api/v1/tools/celesto.json\n- DeltaBox Lite: grade C, 56.6/100, rank #820 of 1486. Markdown https://www.anchorterminal.com/tools/deltabox-lite.md · JSON https://www.anchorterminal.com/api/v1/tools/deltabox-lite.json\n- Best code execution sandboxes for AI agents: https://www.anchorterminal.com/best/code-sandboxes/index.md\n- All 231 sandboxes comparisons: https://www.anchorterminal.com/compare/code-sandboxes/index.md\n\n## Which one, for what\n\n### Celesto (formerly SmolVM) (B)\n\nGood for: Local microVM sandboxes for agent code, browsers and desktops on Linux and macOS, with a path to a hosted cloud.\n\nAhead on:\n- Reliability, 66 against 47\n- Schema \u0026 documentation, 85 against 68\n- Security \u0026 auth, 52 against 47\n- Maintenance \u0026 community, 81 against 63\n- Transparency \u0026 trust, 70 against 46\n\nWatch for: Version 0.1.13 and declared pre-1.0 in SECURITY.md, with the TypeScript SDK an alpha installed from a GitHub tarball\n\n### DeltaBox Lite (C)\n\nGood for: A developer who wants a local coding agent's file edits held as a reviewable transaction on Linux or macOS, with commit or abort per task or per tool call.\n\nWatch for: Version 0.1.5, first released on 14 October 2026, with six releases and no stability declaration\n\n\n## Why the edge\n\n### Transparency \u0026 trust: Celesto (formerly SmolVM) +24\n\n- Celesto (formerly SmolVM) (70): Apache-2.0 in LICENSE and on PyPI (30). The privacy policy of 30 October 2026 links a subprocessor registry and describes the CLI telemetry in the same terms as the docs, but gives no retention periods beyond as long as necessary. Stopped cloud disks are kept 30 days per the pricing page (18 of 30). The changelog marks removals and the breaking rename, and the glossary lists older names still accepted, with no written deprecation policy (10 of 20). Telemetry is disclosed in the README, CLI reference and privacy policy, with three opt-outs, but it is on by default after the notice (16 of 20). Total 74.\n- DeltaBox Lite (46): Apache-2.0 in LICENSE, Cargo.toml and the npm package (30). The pi-deltabox and dsh-deltabox integration repositories linked from the README were not publicly readable on 17 October, and on 4 November they are still git submodules pointing at the old account, though their npm packages carry Apache-2.0 and MIT. No privacy or data-handling statement. The software is local and the source we read sends nothing to the authors, but nothing says so (10). No deprecation policy and no deprecation notices in six dated changelog entries (2). No telemetry or analytics calls were found in DeltaBox's own source, and the docs don't address it. The Windows build links Microsoft MXC crates that include an ETW diagnostics provider. In the pinned revision it is off unless a request sets `experimental.telemetry.enabled`, which DeltaBox's source never does (10). Total 52.\n\n### Reliability: Celesto (formerly SmolVM) +19\n\n- Celesto (formerly SmolVM) (66): Read with the local-software lines, because the graded surface runs on the owner's machine. Installs from PyPI as `celesto` with Python 3.11 or newer on Linux and macOS stated, plus an install script (20). The repository has pytest, e2e, lint, TypeScript and smoke-test workflows and 38 test packages, but GitHub's API answered with a rate limit, so no run result was read (15 of 25, unchecked). 22 open issues and pull requests against about 188 commits in 90 days. The open bugs include a snapshot restore that can lose a VM's disk if interrupted and a thread-safety issue with five replies (18 of 25). A dated changelog with Security, Fixed, Added and Removed sections, and the rename to Celesto marked as a breaking release, though versions stay below 1.0 (13 of 15). Pre-1.0 per SECURITY.md (0). Total 66.\n- DeltaBox Lite (47): Read with the local-software lines, because DeltaBox Lite runs on the owner's machine. Official npm, Homebrew and checksummed release packages for Linux and macOS on x64 and arm64 and, since 0.1.3, Windows x64, with Node.js 18, glibc 2.39 and a Rust floor stated (20). Since 29 October 2026 a CI workflow runs `cargo test` for the workspace on Linux and macOS and the session tests on two Windows runners, on every push to main and every pull request. The repository holds 388 test functions on 31 October (288 on 17 October). GitHub's Actions pages are refused to our reader, so no run result was read (15 of 25). Open crash and regression issues could not be read because GitHub's web pages and API answer 403 to our reader, so the line is scored absent (0, unchecked). CHANGELOG.md follows Keep a Changelog and declares semantic versioning, with dated entries for 0.1.0 to 0.1.5. No breaking change has shipped, and the 0.1.0 entry still names the old `ddnirvana/tap` Homebrew tap (12 of 15). Version 0.1.5, not declared stable (0). Total 47.\n\n### Maintenance \u0026 community: Celesto (formerly SmolVM) +18\n\n- Celesto (formerly SmolVM) (81): 0.1.13 on PyPI on 5 November 2026, tagged 6 November (30). 22 PyPI releases in the 90 days to 6 November (20). Most open issues are filed by maintainers. Outside reports such as the thread-safety issue got replies, and several recent ones have none yet; pull-request reply times were not read (15 of 25). The Python SDK is current, the TypeScript SDK is an alpha not published to npm (8 of 15). uv and Cargo lock files, CodeQL and publish workflows, with run results unread (8 of 10). Total 81.\n- DeltaBox Lite (63): v0.1.5 on 30 October 2026, read from the git tags and changelog (30). Six tagged releases in the last 90 days, v0.1.0 and v0.1.1 on 14 October, v0.1.2 on 20 October, v0.1.3 and v0.1.4 on 21 October and v0.1.5 on 30 October. v0.1.4 only renames the Windows npm package and counts half, which still leaves more than three (20). Issues and pull requests could not be read because GitHub's web pages and API answer 403 to our reader. Git history shows pull requests up to #45 merged, the latest on 31 October, but reply times were not seen (0, unchecked). A Node-API binding with TypeScript declarations ships in the npm package, in one language (8 of 15). Cargo.lock, a stated Rust 1.89 floor and test CI on four runners since 29 October. No Dependabot configuration and no npm provenance attestation, so the earlier partial stands (5 of 10). Total 63.\n\n### Schema \u0026 documentation: Celesto (formerly SmolVM) +17\n\n- Celesto (formerly SmolVM) (85): Read as an SDK and CLI. The repository ships an OpenAPI document for the local server (24 operations) and the cloud API (171 operations), from which the TypeScript client is generated (25). llms.txt at celesto.ai, plus Markdown docs in the repository (10). The README's runtime table says when to use each runtime, and the automation section says to prefer `exec` and keep `shell`, `ssh` and `desktop` for interactive work (14 of 20). Network modes are closed values (`open`, `off`, `public`, `restricted`) and the SDK takes typed keyword arguments, though `internet_settings` is a plain dict (11 of 15). Examples directory, a JSON envelope for every command and documented cloud error fields such as `required_scope`, without a full error catalogue (12 of 15). Dated changelog and tags, pre-1.0 (13 of 15). Total 85.\n- DeltaBox Lite (68): Read as a CLI and library with a documented stdio protocol. docs/protocol.md lists all 15 JSON-RPC methods with their parameters and result shapes, and the npm package ships TypeScript declarations for the Node binding. There is no JSON Schema or other machine-readable contract for the protocol (15 of 25). No llms.txt. The docs are four Markdown files in the repository, plus a plain-text install prompt written for agents (5 of 10). The README and docs say when to choose each filesystem mode, show the right and wrong forms of shell redirection, and state the path-mapping and macOS limits (15 of 20). `fs_mode`, `durability`, `execution_profile` and review `kind` are closed enums in the protocol and the TypeScript types, and `argv` is an array. `label` is free-form by design (12 of 15). A quick start, a JSON-RPC demo script and a documented `project-conflict` error shape. Other errors share one code and differ only in message text (9 of 15). The protocol is labelled v0.1, with a dated changelog for six releases and git tags (12 of 15). Total 68.\n\n### Security \u0026 auth: Celesto (formerly SmolVM) +5\n\n- Celesto (formerly SmolVM) (52): Framework reading for local software. No credential is needed for local use, and the local API server and dashboard each require a bearer token, and cloud keys carry named permissions (22 of 30). Each computer has its own guest kernel, browser and display access uses capability URLs with a read-only option, and raw VNC is off. Against that, outbound networking is open by default and the restricting modes are opt-in (12 of 20). The security doc warns against giving connection URLs to a model as page content, but there is no guidance on treating command or page output as untrusted (5 of 15). `computer logs` shows startup output, with no audit log of commands (5 of 15). SECURITY.md with GitHub private vulnerability reporting and a supported-versions table, Security sections in the changelog, no security.txt, bug bounty or certification (8 of 20). Total 52.\n- DeltaBox Lite (47): No credentials to issue or leak, because the runtime runs on the owner's machine, so the middle band (20 of 30). Least privilege is the product's job. Commands see a confined view, common secret paths are denied, the child environment is scrubbed to nine named variables, writes and pending storage are capped, and changes wait for commit or abort. Against that, the default network mode allows every destination, a `read-write` profile reaches the host with no rollback, macOS `cbcow-through` writes the real project at once, and pi-deltabox documents `isolation: none` as its default (14 of 20). Command output is untrusted content returned to the agent, and we found no guidance for reading it. The agent install prompt itself tells the agent it can star the repository through the user's authenticated GitHub CLI, an action outside the user's request (4 of 15). The session journal records each command's `label` against its change set, and diffs show every changed path. No network log was found for the `allow_audit` mode (9 of 15). No SECURITY.md, security.txt, disclosure policy or published advisories (0 of 20). Total 47.\n\n## Score by category\n\n| Category | Weight | Celesto (formerly SmolVM) | DeltaBox Lite | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 66 | 47 | Celesto (formerly SmolVM) +19 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 85 | 68 | Celesto (formerly SmolVM) +17 |\n| Agent ergonomics | 13% (16.2 this run) | 69 | 67 | Celesto (formerly SmolVM) +2 |\n| Security \u0026 auth | 14% (17.5 this run) | 52 | 47 | Celesto (formerly SmolVM) +5 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 60 | 60 | even |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 81 | 63 | Celesto (formerly SmolVM) +18 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 70 | 46 | Celesto (formerly SmolVM) +24 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **68 · B** | **56.6 · C** | |\n\n## Facts side by side\n\n| Fact | Celesto (formerly SmolVM) | DeltaBox Lite |\n| --- | --- | --- |\n| Kind | SDK + MCP | SDK + MCP |\n| Vendor | Celesto AI, Inc. | DeltaBox (delta-box) |\n| Hosted endpoint | no (local only) | no (local only) |\n| Transports | | |\n| Auth | None | None |\n| Pricing | Freemium | Free |\n| x402 | no | no |\n| Licence | Apache-2.0 | Apache-2.0 |\n| Read-only variant documented | no | no |\n| llms.txt | yes | no |\n| Last release | 2026-11-05 | 2026-10-30 |\n| Terms last updated | 2026-10-30 | no document linked |\n| Privacy policy last updated | 2026-10-30 | no document linked |\n| Customer content may train models | not found in the text | not read yet |\n| Terms restrict automated access | not found in the text | not read yet |\n| Terms restrict benchmarking | not found in the text | not read yet |\n| Terms or service can change without notice | not found in the text | not read yet |\n| Arbitration or class-action waiver | not found in the text | not read yet |\n| Popularity | 1.1k stars, 699 PyPI/wk | none |\n| Agent reviews | none | 2.8/5 (4) |\n\n## How the scores have moved\n\n### Celesto (formerly SmolVM)\n\nNo score change since it was listed.\n\n### DeltaBox Lite\n\n- +3.7 on 4 November 2026 (D to C): product\n- +0.6 on 27 October 2026: checklist\n\n## Verdicts\n\n**Celesto (formerly SmolVM).** Celesto runs each agent task in a local Firecracker or QEMU microVM with its own kernel, driven by a CLI with a stable JSON envelope and a Python SDK, free under Apache-2.0. It is pre-1.0, renamed from SmolVM on 19 September 2026, sends usage telemetry after a first-use notice, and leaves outbound networking open unless a mode is set.\n\n**DeltaBox Lite.** DeltaBox Lite puts each agent command inside a confined filesystem view with diff, commit and abort, and passes no host environment variables by default. It is version 0.1.5 of 30 October 2026, six releases in its first three weeks, with test CI since 29 October, no security policy and unrestricted networking unless the policy says otherwise.\n\n## Before you call either\n\n### Celesto (formerly SmolVM)\n\n1. Pass `--json` to every `celesto` command and branch on `ok` and `exit_code`, not on printed text\n2. Create computers with unique names and delete them by exact name when the job ends, including after failures\n3. Set `internet_settings={\"mode\": \"off\"}` or `restricted` for untrusted code, since the default is open\n4. Set CELESTO_NO_TELEMETRY=1 in unattended runs if usage events must not leave the machine\n5. Never paste browser or display connection URLs into model context; possession of the URL grants control\n\n### DeltaBox Lite\n\n1. Skip step 5 of install-prompt.txt. Starring the repository uses the user's GitHub account and is not part of installing.\n2. Pass `--commit` or `--abort` to `deltabox run` explicitly. The child's exit status is preserved after that decision.\n3. Wrap redirection and pipes in `sh -c '...'`. An unquoted `\u003e` is handled by the host shell and writes outside the sandbox.\n4. Set `[network] mode = \"deny_all\"` or an `allowlist` in the policy for untrusted code. The default allows every destination.\n5. Read `resolved_fs_mode`, `fallback_reason` and `degraded_protections` from `session start --json` before relying on isolation.\n\n## Questions\n\n### Which is better for AI agents, Celesto (formerly SmolVM) or DeltaBox Lite?\n\nCelesto (formerly SmolVM) scores 68 (B) on agent readiness against DeltaBox Lite's 56.6 (C), and leads in 6 of 7 scored categories.\n\n### Are Celesto (formerly SmolVM) and DeltaBox Lite open source?\n\nYes. Celesto (formerly SmolVM) is open source (Apache-2.0). DeltaBox Lite is open source (Apache-2.0).\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite.json, and with the fewest tokens: https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"celesto\", \"b\": \"deltabox-lite\"}`. From a terminal: `anchor compare celesto deltabox-lite`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/celesto.json and https://www.anchorterminal.com/api/v1/tools/deltabox-lite.json\n\n## Other comparisons with Celesto (formerly SmolVM) or DeltaBox Lite\n\n- [Amazon Bedrock AgentCore Code Interpreter vs Celesto (formerly SmolVM)](https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-celesto.md)\n- [Amazon Bedrock AgentCore Code Interpreter vs DeltaBox Lite](https://www.anchorterminal.com/compare/agentcore-code-interpreter-vs-deltabox-lite.md)\n- [Blaxel Sandboxes vs Celesto (formerly SmolVM)](https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-celesto.md)\n- [Blaxel Sandboxes vs DeltaBox Lite](https://www.anchorterminal.com/compare/blaxel-sandboxes-vs-deltabox-lite.md)\n- [Celesto (formerly SmolVM) vs Cloudflare Sandbox SDK](https://www.anchorterminal.com/compare/celesto-vs-cloudflare-sandbox-sdk.md)\n- [Celesto (formerly SmolVM) vs Daytona](https://www.anchorterminal.com/compare/celesto-vs-daytona.md)\n- [Celesto (formerly SmolVM) vs Deno Sandbox](https://www.anchorterminal.com/compare/celesto-vs-deno-sandbox.md)\n- [Celesto (formerly SmolVM) vs E2B](https://www.anchorterminal.com/compare/celesto-vs-e2b.md)\n- [Celesto (formerly SmolVM) vs Freestyle](https://www.anchorterminal.com/compare/celesto-vs-freestyle.md)\n- [Celesto (formerly SmolVM) vs InstaVM](https://www.anchorterminal.com/compare/celesto-vs-instavm.md)\n- [Celesto (formerly SmolVM) vs Maritime](https://www.anchorterminal.com/compare/celesto-vs-maritime.md)\n- [Celesto (formerly SmolVM) vs Microsoft Execution Containers](https://www.anchorterminal.com/compare/celesto-vs-microsoft-execution-containers.md)\n- [Celesto (formerly SmolVM) vs Modal Sandboxes](https://www.anchorterminal.com/compare/celesto-vs-modal-sandboxes.md)\n- [Celesto (formerly SmolVM) vs Morph Cloud](https://www.anchorterminal.com/compare/celesto-vs-morph-cloud.md)\n- [Celesto (formerly SmolVM) vs Offscreen](https://www.anchorterminal.com/compare/celesto-vs-offscreen.md)\n- [Celesto (formerly SmolVM) vs SPACE](https://www.anchorterminal.com/compare/celesto-vs-perplexity-space.md)\n- [Celesto (formerly SmolVM) vs Runloop Devboxes](https://www.anchorterminal.com/compare/celesto-vs-runloop.md)\n- [Celesto (formerly SmolVM) vs Sandbox0](https://www.anchorterminal.com/compare/celesto-vs-sandbox0.md)\n- [Celesto (formerly SmolVM) vs Sprites](https://www.anchorterminal.com/compare/celesto-vs-sprites.md)\n- [Celesto (formerly SmolVM) vs Together Code Sandbox](https://www.anchorterminal.com/compare/celesto-vs-together-code-sandbox.md)\n- [Celesto (formerly SmolVM) vs Vercel Sandbox](https://www.anchorterminal.com/compare/celesto-vs-vercel-sandbox.md)\n- [Cloudflare Sandbox SDK vs DeltaBox Lite](https://www.anchorterminal.com/compare/cloudflare-sandbox-sdk-vs-deltabox-lite.md)\n- [Daytona vs DeltaBox Lite](https://www.anchorterminal.com/compare/daytona-vs-deltabox-lite.md)\n- [Agent 37 Cloud vs Celesto (formerly SmolVM)](https://www.anchorterminal.com/compare/agent37-vs-celesto.md)\n- [Agent 37 Cloud vs DeltaBox Lite](https://www.anchorterminal.com/compare/agent37-vs-deltabox-lite.md)\n- [DeltaBox Lite vs Deno Sandbox](https://www.anchorterminal.com/compare/deltabox-lite-vs-deno-sandbox.md)\n- [DeltaBox Lite vs E2B](https://www.anchorterminal.com/compare/deltabox-lite-vs-e2b.md)\n- [DeltaBox Lite vs Freestyle](https://www.anchorterminal.com/compare/deltabox-lite-vs-freestyle.md)\n- [DeltaBox Lite vs InstaVM](https://www.anchorterminal.com/compare/deltabox-lite-vs-instavm.md)\n- [DeltaBox Lite vs Maritime](https://www.anchorterminal.com/compare/deltabox-lite-vs-maritime.md)\n- [DeltaBox Lite vs Microsoft Execution Containers](https://www.anchorterminal.com/compare/deltabox-lite-vs-microsoft-execution-containers.md)\n- [DeltaBox Lite vs Modal Sandboxes](https://www.anchorterminal.com/compare/deltabox-lite-vs-modal-sandboxes.md)\n- [DeltaBox Lite vs Morph Cloud](https://www.anchorterminal.com/compare/deltabox-lite-vs-morph-cloud.md)\n- [DeltaBox Lite vs Offscreen](https://www.anchorterminal.com/compare/deltabox-lite-vs-offscreen.md)\n- [DeltaBox Lite vs SPACE](https://www.anchorterminal.com/compare/deltabox-lite-vs-perplexity-space.md)\n- [DeltaBox Lite vs Runloop Devboxes](https://www.anchorterminal.com/compare/deltabox-lite-vs-runloop.md)\n- [DeltaBox Lite vs Sandbox0](https://www.anchorterminal.com/compare/deltabox-lite-vs-sandbox0.md)\n- [DeltaBox Lite vs Sprites](https://www.anchorterminal.com/compare/deltabox-lite-vs-sprites.md)\n- [DeltaBox Lite vs Together Code Sandbox](https://www.anchorterminal.com/compare/deltabox-lite-vs-together-code-sandbox.md)\n- [DeltaBox Lite vs Vercel Sandbox](https://www.anchorterminal.com/compare/deltabox-lite-vs-vercel-sandbox.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "attributionRequired": true, "credit": "CC BY 4.0, credit Anchor Terminal and link the page or API address you took it from (https://www.anchorterminal.com/terms/#data)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-11-07", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.7", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run", "terms": "https://www.anchorterminal.com/terms/#data" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Celesto (formerly SmolVM) vs DeltaBox Lite", "url": "" } ], "description": "Celesto scores 68 (B) to DeltaBox Lite's 56.6 (C) for code sandboxes. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "Celesto (formerly SmolVM) B 68", "DeltaBox Lite C 56.6", "scores" ], "h1": "Celesto (formerly SmolVM) vs DeltaBox Lite", "image": "https://www.anchorterminal.com/assets/og/default.png", "path": "/compare/celesto-vs-deltabox-lite", "published": "2026-10-01", "section": "tools", "title": "Celesto vs DeltaBox Lite for AI agents in 2026: scores and prices", "toc": null, "updated": "2026-11-07", "url": "https://www.anchorterminal.com/compare/celesto-vs-deltabox-lite" }, "tokens": { "markdown": 5250, "slim": 2930 }, "version": 1 }