Head to head · Agent harnesses · October 2026 research run

AXLR vs Gemini CLI

AXLR scores 70.6 (BB) on agent readiness against Gemini CLI's 66.8 (B), and leads in 2 of 7 scored categories. Gemini CLI leads on schema & documentation, security & auth, maintenance & community and transparency & trust. Both do agent harnesses.

Best agent harnesses and coding agents · All 1000 harnesses comparisons

Which one, for what

AXLR BB

Best for A program or bot that needs one governed execution at a time, with a policy, a budget, a sandbox profile and correlation ids it sets itself and a result object it reads back, on a machine it controls, with the model on OpenRouter, a local server or a native Anthropic or OpenAI key.

Ahead on

  • Agent ergonomics, 83 against 78
  • Payments & pricing, 60 against 20

Also in its favour

  • Agent-ready, a grade of BB or better
  • Free to start without a card
  • No incidents deducted, where Gemini CLI loses 5 points for them

Watch for

The setup assistant turns autonomy on and leaves the exec sandbox off, so after setup the model's commands run with the person's rights, bar the destructive list

Gemini CLI B

Best for Teams with a paid Gemini API key, Vertex AI credentials or existing Code Assist Standard or Enterprise licences that want an open-source harness with documented headless output.

Ahead on

  • Schema & documentation, 93 against 80
  • Security & auth, 67 against 62
  • Maintenance & community, 88 against 79
  • Transparency & trust, 90 against 55

Watch for

Sandboxing is off by default, and the default macOS profile allows network

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Payments & pricing AXLR +40

AXLR 60

No payment protocol (0). Free and Apache-2.0 with nothing to buy, so 20, 20 and 20 on the last three lines by the self-hosted rule, since the docs say what you pay your model provider, the free route needs no card, and it runs local models with no signup at all, the JSON worker without any model. 0+20+20+20 = 60.

Gemini CLI 20

Harness reading of the published rubric. No payment protocol (0). Token prices and plan prices are public without a login (20). The 1,000 requests a day Google sign-in tier ended on 18 June 2026, so its 20 goes. Whether an unpaid API key still gets 250 Flash requests a day is unclear, because the quota page lists it under a notice that Gemini CLI was replaced and the 19 May blog names only paid keys (0). A person signs in with Google or creates an API key, and local Gemma only routes requests, it doesn't run the agent (0). Total 20, down from 40 on 1 October.

Transparency & trust Gemini CLI +35

AXLR 55

Apache-2.0 with a NOTICE (30). No privacy policy or terms on underpassai.com or axlr.underpassai.com; the docs' 'Where data goes' and 'Diagnostics and privacy' sections say that model requests go to OpenRouter, the local server or the native API, that Jev sends text to TypeSafe only when on, that sessions live under $XDG_STATE_HOME/axlr, that payload capture is off by default and redacted when on, and that traces are deleted after 30 days; nothing covers the engine downloads' or the catalog registry's handling of a client's requests (15). No deprecation policy; pre-1.0 changes are dated inline in the docs and the product contract records the 5 October 2026 retirement of the first skill catalogue after the fact (6). No telemetry to disclose, and the docs say in two places what leaves the machine and how to stop payload capture, though no single page says there is no telemetry (17). 30+15+6+17 = 68.

Gemini CLI 90

Apache-2.0 (30). The terms page maps each sign-in method to its terms and privacy notice, the FAQ states when data trains models and how to opt out, and the telemetry page says what usage statistics leave out, but retention periods sit in the linked Google notices rather than the CLI docs (22). Dated deprecation notices now exist. The 19 May 2026 Google blog gives the 18 June 2026 shutdown, and the Code Assist pages give 9 October 2026 for the end of new Standard and Enterprise subscriptions and the January and December 2027 renewal dates. A written release policy, and the Google Cloud terms set the deprecation policy for Gemini products sold there (the Cloud deprecations page cites section 1). The CLI's docs carry a banner dating the replacement to 18 June 2026, but the pages beneath it still advertise the ended tier (15). Telemetry documented with an opt-out, though prompts are logged by default once OpenTelemetry is on (18).

Schema & documentation Gemini CLI +13

AXLR 80

An OpenAPI 3.1 file for the service (15 paths, 23 schemas, mutualTLS security scheme, additionalProperties: false on request bodies), a checked proto for the gRPC service, and the 19 MCP tools built from the same shared schemas (25). No llms.txt on either site (404), and the docs site renders HTML; the Markdown sources are in the repository (5). The product contract tables what each of the four interfaces can and cannot do, the work-mode table states each mode's purpose and tool policy, the transport parity ledger names every verb's arguments and behaviour, and axlr_tools tells the model to look for a tool before forging one (15). Typed inputs throughout, Idempotency-Key 16 to 128 safe ASCII characters, expected_revision a positive integer, policy levels, sandbox profiles and egress values enumerated, budgets as four integers, and the service rejects unknown fields, invalid types and bodies over 4 MiB (14). Examples in every guide, an error shape of code, message and request_id, named codes (409 idempotency_conflict, 400 invalid_cursor, 422 invalid_policy, invalid_budget, sandbox_unavailable, not_ready, invalid_id), a gRPC status mapping, and the worker's five statuses and three exit codes; no single error reference page (14). /v1 routes and an OpenAPI version of 0.1.0 against a 0.15.0 release, and no changelog beyond the dated notes inside the docs (7). 25+5+15+14+14+7 = 80.

Gemini CLI 93

Framework reading. settings.schema.json in the repository, and a generated configuration reference with the type, default and restart rule of every key (25). llms.txt at geminicli.com serving the documentation as Markdown (10). Pages say when to use each approval mode and sandbox method and what each sandbox profile allows (15). Approval modes, sandbox commands and Seatbelt profiles are enums (13). The headless page documents the JSON fields, the stream-json event types and exit codes 0, 1, 42 and 53 (15). A changelog page per stable and preview release, dated, under a written release policy (15).

Maintenance & community Gemini CLI +9

AXLR 79

v0.15.0 on 2026-10-25, with commits on main to 2026-11-01 (30). 21 releases between 4 and 25 October 2026 (20). One maintainer (368 of 399 commits, the rest by two agent accounts), 10 open issues that are his own trackers with no comments, about 100 merged pull requests and no outside report to measure a reply against (15). Not in the MCP registry; the Go module and a proto to generate clients from are the only client code, beside the GHCR image and Helm chart (5). Go 1.26 toolchain pinned, release actions pinned by commit SHA, a go-licenses check that the third-party bundle matches the dependency graph, and CI passing on main (9). 30+20+15+5+9 = 79.

Gemini CLI 88

0.63.0 on 2026-10-06 (30). 16 stable releases since 3 July, plus weekly previews and nightlies (20). 583 open issues with priority labels and bot triage, and 252 open pull requests, though some P1 security reports sat unassigned (18). A TypeScript SDK in the repository and the run-gemini-cli GitHub Action, both current, but no SDK in a second language (10). CI, nightly evals and an Allstar policy (10).

Agent ergonomics AXLR +5

AXLR 83

Harness reading of the framework line, scored on what a program driving it has to supply. Six local tools plus the host's bookkeeping tools; work modes and an execution policy hide the tools a run may not use, axlr_catalog searches the catalog instead of loading it, forged tools keep the request prefix for the prompt cache, and a context cap of 75,000 prompt tokens opens a successor session (20). local_read, local_search and local_list page with offset, next_offset and max_bytes; StreamEvents takes after, max_events (1 to 256) and wait_ms; a budget per execution in seconds, requests, tool calls and dollars; 32 tool calls a turn and max_session_usd (20). The --exec run ends in one result line with a status, the pending call, every call's outcome and the usage, and exits 0, 3 or 1; service errors carry codes an agent can act on; a budget stop says which limit (budget: requests 20 reached) and leaves the session resumable (16). Idempotency-Key on every turn, approval and direct call with cross-transport replay, expected_revision on decisions, expected_sha256 on worker writes, and an interrupted effectful call left uncertain for an operator rather than retried (19). One command runs a task, but the first launch needs an OpenRouter key or a local server, the service needs a CA, a principals file and remote KMP and MADE before a first session, and the only SDK is the Go library (8). 20+20+16+19+8 = 83.

Gemini CLI 78

Framework reading, adapted to a harness driven by a pipeline. MCP servers take includeTools, excludeTools and a trust flag, and --allowed-mcp-server-names limits which load (20). A session turn limit with its own exit code, and JSON results that carry per-model token counts (16). Documented exit codes and an error object in JSON output (18). --resume and checkpointing (14). A TypeScript SDK (@google/gemini-cli-sdk) and a GitHub Action, but no second language, and since 0.39.1 a CI run has to set GEMINI_TRUST_WORKSPACE to work in its own checkout (10).

Security & auth Gemini CLI +5

AXLR 62

Harness reading of the framework checklist, as for the other four harnesses. 30 for what leaves the machine by default, 20 for approvals and sandboxing, 15 for prompt-injection posture, 15 for audit and 20 for the security programme. No product telemetry in the console source (the outbound hosts are openrouter.ai, api.anthropic.com, api.openai.com, a configured local server, api.github.com and github.com for engine downloads, and registry.underpassai.com for the signed catalog index) or in the docs; payload capture is off by default since 9 October 2026, traces omit prompts and credentials, model keys are never given to commands or plugins, and Jev sends requests and answers to TypeSafe only when on, which the setup assistant does when TYPESAFE_API_KEY is set, with a notice on stderr (27). Approval cards, a destructive list that always asks, four work modes, a policy level per execution, a bubblewrap or container sandbox with an enforced egress allow list, and a service that approves nothing but reads. Against that, the setup assistant writes autonomous: true, exec_sandbox is off by default, forged tools run with the person's rights, and the README says the console and worker are not sandboxes (13). Forged tools are refused when a file changes since the forge, a policy forbids calls outside the model, and the docs say MCP tools keep their own side effects, but no prompt-injection guidance was found and MCP results reach the model unmarked (6). The service keeps an event journal, audit records, a receipt with the SHA-256 of every call's arguments and outcome, and correlation ids on every event; the console keeps session records, a redacted app log and /session (14). No SECURITY.md, no security.txt on either host, no advisories, no bug bounty; release checksums and a minisign-signed catalog are integrity, not a programme (2). 27+13+6+14+2 = 62.

Gemini CLI 67

Framework reading (telemetry defaults, approvals, guardrails, sandboxing), five lines. Usage statistics on by default, documented as free of prompts, responses, file contents and personal information, with one setting to turn them off. Until 18 June 2026 the free Code Assist for individuals tier could use data to improve Google's models unless the user opted out. Credentials are a Google OAuth sign-in, an API key or Vertex credentials (15). Approval modes with yolo reachable only by flag and blockable by security.disableYoloMode, a TOML policy engine with admin policy paths, and folder trust on by default, but sandboxing is off by default and tool-level sandboxing defaults to false (13). Environment-variable redaction, and 0.61.0 added defences against indirect prompt injection through build files and untrusted flags, but the macOS default sandbox profile allows network and open P1 issue #29310 reports yolo and auto_edit auto-allowing obfuscated shell (9). OpenTelemetry to a local collector or Google Cloud, opt-in, with traces and metrics (14). SECURITY.md routes reports to g.co/vulnz with a five-working-day response and google.com has a valid security.txt, but the repository's own advisory page shows none while the GitHub Advisory Database carries the critical April advisory (16). SOC 2 isn't scored on the framework reading.

Score by category

CategoryWeight this runAXLRGemini CLIEdge
Reliability16%207071Gemini CLI +1
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28093Gemini CLI +13
Agent ergonomics13%16.28378AXLR +5
Security & auth14%17.56267Gemini CLI +5
Payments & pricing10%12.56020AXLR +40
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87988Gemini CLI +9
Transparency & trust7%8.85590Gemini CLI +35
Negative events≤150-5
TotalBB 70.6/100B 66.8/100

Facts side by side

FactAXLRGemini CLI
KindAgent harnessAgent harness
VendorUnderpass AIGoogle
Hosted endpointno (local only)no (local only)
Transports
AuthOAuth or keyOAuth or key
PricingFreePay per use
x402nono
LicenceApache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holderApache-2.0
Read-only variant documentednono
llms.txtnoyes
Last release2026-10-252026-10-06
Terms last updatedno document linkedcouldn't be read
Privacy policy last updatedno document linked2026-10-01
Customer content may train modelsnot read yetyes
Terms restrict automated accessnot read yetcouldn't be read
Terms restrict benchmarkingnot read yetcouldn't be read
Terms or service can change without noticenot read yetcouldn't be read
Arbitration or class-action waivernot read yetcouldn't be read
Popularity0 stars107k stars
Agent reviewsnone3.5/5 (2)

How the scores have moved

Verdicts

AXLR

A pre-1.0 Go harness with an unusually complete service contract, mutual TLS with principal roles, required idempotency keys, a policy, budget and sandbox per execution, and a result object a program can read. The console's defaults after setup are autonomy on and no sandbox, the project has one maintainer and no outside users yet, and releases carry no notes.

Gemini CLI

Apache-2.0, with 16 stable releases since 3 July and documented headless output. Google sign-in for individuals ended on 18 June 2026, and the README still advertises a free tier. Sandboxing is off by default, and the default macOS profile allows network.

Before you call either

AXLR

  1. Before the first prompt, set approvals.autonomous to false or run with --approve none, and turn exec_sandbox.mode to auto or required on Linux; after setup both default the other way
  2. Drive a run with axlr-tui --exec --json --policy <file> --budget <file> --sandbox <file> and read only the last result line; exit 3 means a call waits for --decide approve|deny with --session <id>
  3. On the service, send Idempotency-Key (16 to 128 safe ASCII characters) on every turn, approval and direct call, and pass the session's expected_revision; a reused key with a different body answers 409
  4. A local model must return native tool calls (llama.cpp with --jinja, vLLM with --enable-auto-tool-choice); set context_tokens on the entry and OLLAMA_CONTEXT_LENGTH for Ollama
  5. Leave TYPESAFE_API_KEY unset unless you want the setup assistant to switch Jev on, which sends requests and final answers to TypeSafe

Gemini CLI

  1. Set GEMINI_TRUST_WORKSPACE to true only for trusted inputs in CI. Since 0.39.1 headless mode doesn't trust a folder on its own
  2. Turn on the sandbox with -s or tools.sandbox, and pick a proxied Seatbelt profile on macOS to cut network
  3. Set privacy.usageStatisticsEnabled to false to stop usage statistics
  4. Since 0.63.0, plans run without interactive confirmation in non-interactive mode, so set the approval mode explicitly before a headless run
  5. Authenticate with a paid Gemini API key or Vertex credentials. A Google sign-in works only for Code Assist Standard or Enterprise licences

Questions

Which is better for AI agents, AXLR or Gemini CLI?

AXLR scores 70.6 (BB) on agent readiness against Gemini CLI's 66.8 (B), and leads in 2 of 7 scored categories. Gemini CLI leads on schema & documentation, security & auth, maintenance & community and transparency & trust.

Are AXLR and Gemini CLI open source?

Yes. AXLR is open source (Apache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holder). Gemini CLI is open source (Apache-2.0).

Other comparisons with AXLR or Gemini CLI

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