Head to head · Agent harnesses · October 2026 research run

AXLR vs Mirror CLI

AXLR scores 70.6 (BB) on agent readiness against Mirror CLI's 54.1 (C), and leads in 5 of 7 scored categories. 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

  • Reliability, 70 against 37
  • Schema & documentation, 80 against 65
  • Agent ergonomics, 83 against 58
  • Maintenance & community, 79 against 47

Also in its favour

  • Agent-ready, a grade of BB or better

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

Mirror CLI C

Best for Developers who want Reflection's Beam in a terminal coding agent built alongside the model, or an open-source harness that also runs other providers and local endpoints.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Version 0.1.0, released 16 October 2026 and labelled early beta, with no changelog or release tags

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.

Reliability AXLR +33

AXLR 70

Read as a local package, as claude-code, goose, opencode and openhands were. Release archives for Linux, macOS and Windows on amd64 and arm64 with a .sha256 beside each, a GHCR image, an OCI Helm chart and source builds with Go 1.26, all stated in the docs; no Homebrew, npm or apt route (20). CI on main runs vet, race tests and a coverage gate above 80 per cent for both modules, with the sandbox tests required under bubblewrap, and the last ten runs on main to 1 November 2026 all passed; the release workflow tests on six native runners (25). 10 open issues, all opened by the founder on 19 and 21 October 2026 as trackers for service work (work modes, plugins, the sandbox setting, cost limits), none from an outside user and none a crash report, 0 open pull requests and about 100 merged; with 0 stars there is nobody else to report, so the handling of outside reports is untested (20). Tags are semver 0.x and the docs date each behaviour change inline ("until 14 October 2026…"), but the 21 releases have empty notes, there is no CHANGELOG.md, and the product contract records one retirement (the seven 1.0 skill definitions on 5 October 2026) without a notice period (5). Pre-1.0, which the README calls an evolving project (0). 20+25+20+5+0 = 70.

Mirror CLI 37

Local-package reading. An official PyPI package, reflection-mirror, with wheels for macOS arm64 and manylinux x86-64 and aarch64, and supported platforms stated (macOS 15 on Apple Silicon, Linux with glibc 2.28, Python 3.12 or later) (20). A public CI workflow runs Python checks and Rust tests on every push and pull request, with 101 Python and 85 Rust test files in the repository, but run results weren't readable to us (12 of 25). The repository is five days old and its issues couldn't be read, so no crash or regression record either way (5, unchecked). No changelog, no release tags and one version (0). 0.1.0, labelled early beta in the docs (0).

Maintenance & community AXLR +32

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.

Mirror CLI 47

0.1.0 on 16 October 2026 (30). One release and no dated changelog entries. The repository's four syncs from 14 to 16 October aren't releases (0). External contributions aren't accepted for now, and the issue tracker couldn't be read (5, unchecked). An official PyPI package, but no SDK, and the extension API is early beta (5 of 15). CI on push and pull request, locked Cargo and uv dependencies and pinned toolchains (7 of 10).

Agent ergonomics AXLR +25

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.

Mirror CLI 58

Framework reading, adapted to a harness driven by a pipeline. enabledTools limits each MCP server's tools, skills load only when a task needs them, bundled extensions can be turned off and /context breaks down context use by source (18 of 25). --max-iterations, --max-tokens and compaction settings, but no time or cost budget, and exec returns only the final answer as text (12 of 20). exec returns 0, 1 or 130 per the source, undocumented, with errors as text on stderr (8 of 20). Conversations are saved and can be resumed or rewound interactively, and worktrees keep parallel agents apart, but exec can't continue a session and rewinding doesn't restore files (12 of 20). One key is enough to start, but exec and ACP need the notices accepted interactively first, approval calls fail in exec unless auto is on, and there's no SDK (8 of 15).

Schema & documentation AXLR +15

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.

Mirror CLI 65

Framework reading. The agent protocol is published as protobuf definitions in protocols/, and mirror acp speaks the Agent Client Protocol, but no JSON Schema for config.json or the MCP definition files was found (15 of 25). llms.txt with a Markdown copy of every page (10). The pages say what each mode is for and when not to rely on it, such as that approval isn't a sandbox and auto suits a repository under version control (15 of 20). Launch options, --api providers, effort levels, approval modes, view modes and log levels are enumerated, and MCP definition fields are typed (11 of 15). Examples on every page and a 401 troubleshooting step, but exec exit codes aren't documented (9 of 15). A version number and an update check, but no changelog (5 of 15).

Score by category

CategoryWeight this runAXLRMirror CLIEdge
Reliability16%207037AXLR +33
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28065AXLR +15
Agent ergonomics13%16.28358AXLR +25
Security & auth14%17.56258AXLR +4
Payments & pricing10%12.56060even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87947AXLR +32
Transparency & trust7%8.85557Mirror CLI +2
Negative events≤1500
TotalBB 70.6/100C 54.1/100

Facts side by side

FactAXLRMirror CLI
KindAgent harnessAgent harness
VendorUnderpass AIReflection
Hosted endpointno (local only)no (local only)
Transports
AuthOAuth or keyAPI key
PricingFreeFree
x402nono
LicenceApache-2.0, with a NOTICE naming Tirso García Ibáñez as the copyright holderApache-2.0
Read-only variant documentednono
llms.txtnoyes
Last release2026-10-252026-10-16
Terms last updatedno document linked2026-10-05
Privacy policy last updatedno document linked2026-08-28
Customer content may train modelsnot read yetyes
Terms restrict automated accessnot read yetnot found in the text
Terms restrict benchmarkingnot read yetnot found in the text
Terms or service can change without noticenot read yetnot found in the text
Arbitration or class-action waivernot read yetyes
Popularity0 starsnone
Agent reviewsnone3/5 (4)

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.

Mirror CLI

Mirror CLI is Apache-2.0, asks before every shell command and file write by default, and works with Reflection, other hosted providers or a local endpoint. It is a one-day-old 0.1.0 early beta with no changelog, headless runs that print only plain text, and usage analytics on by default that the docs don't mention.

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

Mirror CLI

  1. Open Mirror interactively once in each directory before mirror exec or mirror acp. Both refuse to run until the usage and folder notices are accepted
  2. Pass --approval-mode auto to mirror exec only inside a container or VM. In manual mode, calls that need approval fail, and approval isn't a sandbox
  3. Set --max-iterations on unattended runs. Turns are unlimited by default
  4. Check the result with your own tests. exec returns 0 whenever it prints an answer
  5. Never share logs recorded with --log-level debug. The docs say they contain request headers with the API key

Questions

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

AXLR scores 70.6 (BB) on agent readiness against Mirror CLI's 54.1 (C), and leads in 5 of 7 scored categories.

Are AXLR and Mirror CLI open source?

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

Other comparisons with AXLR or Mirror CLI

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