Amp vs Sculptor

Amp 72

Framework reading. A JSON Schema for the settings file at ampcode.com/cli-settings.schema.json (22 properties), TypeScript types for every stream message, and a generated reference for the plugin API, but no OpenAPI for the server (18). ampcode.com/llms.txt indexes a raw Markdown rendition of each of 55 docs pages (10). The docs say when to use execute mode, orbs, runners, the oracle and the Librarian, and what each mode is for (15). Settings carry types and defaults, and the stream schema enumerates stop reasons, result subtypes and MCP server states (12). Examples on nearly every page and two result error subtypes (error_during_execution, error_max_turns), with no exit codes or error catalogue (9). Dated Chronicle posts with an RSS feed and a lastModified date on each docs page, but no changelog by CLI version (8).

Sculptor 45

Harness reading. A README, specs and agent docs in the repository; no API reference (45).

Amp 35

Harness reading of the published rubric. No payment protocol (0). The pricing page is public. Hobby is free, Megawatt is $20 a month with 45,000 orb minutes, orbs are priced per hour by size from $0.08, and paid credits are charged at provider API prices with no markup outside Enterprise. Gigawatt is $200 a month with $200 of agent usage and 1,000 hours of a1.xxlarge orbs, per the pricing docs (20). Hobby is free when you bring your own model key or subscription and run locally or on your own runner. The pricing page does not say whether sign-up asks for a card, and inference served by Amp is never free (15). A person signs in through a browser to create the access token (0).

Sculptor 60

Free self-hosted software with nothing to buy, so 0 for a protocol and 20 each for public pricing, a free tier and onboarding with no sign-up, 60.

Amp 23

Local-package reading, as for the other closed-source harnesses. An install script that verifies a SHA-256 checksum, and an @ampcode/cli npm package of prebuilt binaries, for macOS, Linux and Windows through WSL, per the 8 October check (20). The source repository is private, so there is no public CI or test suite (0). There is no public issue tracker, and bug reports go to the vendor from inside the product. The 8 October reading of the status page's incident feed is struck, because ampcodestatus.com's robots.txt now disallows ClaudeBot, Claude-Web and anthropic-ai, so nothing is left to count crash or regression reports against (0). Versions are build stamps such as 0.0.1792627309-g98c009 with no per-version notes, and the introduction says "No backward compatibility", though removals are announced with dates in the Chronicle (3). The version line is 0.0 and we found no statement that the CLI is stable (0).

Sculptor 43

Local software. Desktop downloads for Mac (Apple Silicon), Linux and Linux ARM64 (20). checks.yml and a PR gate run on the repository; pass state not read (15). GitHub issues and pull requests weren't read (GitHub's pages refuse these sessions), so that line is scored absent (0). sculptor-v tags up to v0.49.0, no changelog file (8). 0.x and labelled a research preview (0). 20 + 15 + 0 + 8 + 0 = 43.

Amp 77

Closed source under the Amp licence terms from Amp Frontier Corporation, with the npm packages marked Amp Commercial License. The terms page shows no date (15). The security reference lists 19 providers and what each sees, says deleted threads are removed within 30 days, diagnostic data after 7 days and audit logs kept at least 30 days, and the privacy policy (modified 10 September 2026) agrees, with account data kept while the account is active (24). No deprecation policy. The terms allow any part of the Services to be discontinued without notice, while removals so far were announced with dates, such as the old npm package names on 14 May 2026 for removal on 15 June (8). Amp is local software tied to a hosted service. Providers and US hosting are disclosed in detail, but the usage data the client sends is not itemised and has no documented opt-out (12).

Sculptor 57

MIT (30). Consent-based telemetry documented in the repository (18 of 30). The README warns of drastic changes during the research preview, with no deprecation policy (5). Opt-in telemetry (20). 30 + 18 + 5 + 20 = 73.

Amp 69

Harness reading of the framework line. amp.tools.disable removes built-in or MCP tools by name or glob, and MCP servers can be allowed or rejected by pattern or attached per run with --mcp-config (17). The stream schema has an error_max_turns result, but we found no documented flag for a turn or spend limit. Workspace entitlements set per-user quotas (9). --stream-json output follows Claude Code's format where it can, --stream-json-input takes several user messages on stdin, and the final message carries is_error, turns, duration and token usage (15). Threads continue by ID with amp threads continue, hand off to a new thread, and can move between the CLI, a runner and an orb (16). TypeScript and Python SDKs wrap the CLI, and a run needs an Amp account and an access token (12).

Sculptor 50

Harness reading. Workspaces as isolated copies, review and merge back, and built-in skills (50).