# Harness guide for coding agents Source: https://redcrown.ai/docs/guides/harness-for-agents/ This page is for a coding agent that runs the RedCrown harness loop for a builder. Copy the commands as written. The same text ships in the `redcrown` package as `redcrown/harness/AGENTS.md`. The canonical page is [https://redcrown.ai/docs/guides/harness-for-agents/](https://redcrown.ai/docs/guides/harness-for-agents/). ## Install Run `pip install redcrown`. It needs Python 3.11 or newer. Confirm the install with `redcrown harness --help`. Every `harness` command, `score`, and `check` run offline with no account and no provider key. Only `push` needs an account. ## The three harness commands Each command reads a journal directory: one subdirectory per run, holding `meta.json` and one or more `verdicts*.jsonl` files. Pass the journal directory with `--runs`. The run id is the subdirectory name. These are the required flags: ``` redcrown harness report --runs redcrown harness compare --runs redcrown harness export --runs --name "" \ --label "@" --out ``` Optional flags: `--rulings ` on all three; `--format text|markdown|json` and `--allow-corpus-drift` on `compare`; `--quality-bar` and `--task-summary` on `export`. On `report`, `--policy `, `--baseline `, and `--format text|json` check the run against a written policy. Needs redcrown 0.1.23 or later. Ruling notes from `compare` go to stderr, so `--format json` stays parseable on stdout. ## Exit codes - `report` without `--policy`: 0. It exits 1 when the run is not found under `--runs`. - `report --policy `: 0 when every rule in the policy passed. 2 when a rule failed or a rule is indeterminate. 1 on an input or policy error: the run or the baseline run is not found, the policy file cannot be read, the policy is YAML or not valid, or the policy has a `no_regression` rule and no `--baseline`. `--baseline` or `--format json` without `--policy` also exits 1. - `compare`: 0 when nothing regressed. 1 on any regression. 2 when the compare is refused because the two runs carry different corpus versions; pass `--allow-corpus-drift` to compare the shared case ids anyway. - `export`: 0. It exits 1 when the run is not found. - `check` (`redcrown check --policy `): 0 on pass. 2 on fail or indeterminate. 1 on a command, file, or policy error. It reads the private evidence file from `redcrown score --evidence-json` or `redcrown eval --evidence-json`, never a journal or an export. - `push`: 0 when the run was pushed. 1 when not logged in, when the request failed, on a plan limit, or when the proof link was refused by the publish gate. Read the process exit code. Do not parse the last line of the output for it. A policy result and a compare result are different results. `compare` says whether anything regressed against an earlier run. `report --policy` says whether the run meets the requirements the owner wrote. A rule with no evidence is indeterminate, never a pass. This policy file asks for no `ERROR` case and an `ok` rate of at least 50% on the `persisted` check over at least 3 measurements: ``` { "schema_version": 1, "kind": "harness", "requirements": { "maximum_status_rate": {"ERROR": 0}, "check_minimum_rate": [{"name": "persisted", "threshold": 0.5, "minimum_measured": 3}] } } ``` On a run with one `PASS`, one `FAIL`, and one `BLOCKED` case, `persisted` has 2 measurements, so the second rule has too little evidence. The command prints the report summary, then this block, and exits 2: ``` redcrown harness policy: indeterminate (exit 2) maximum_status_rate.ERROR: pass; observed 0; threshold 0; 0 of 3 check_minimum_rate[0]: indeterminate; reason insufficient_measurements; threshold 0.5; 1 of 2 ``` Add `--format json` to get one JSON document with the status, the exit code, and every rule. ## Statuses A case is a list of named checks. Each check is `ok`, `fail`, or `unmeasured`. The case status is derived in this order: an error is `ERROR`; any fail is `FAIL`; nothing measured is `BLOCKED`; something measured and the rest unmeasured is `PARTIAL`; otherwise `PASS`. An unmeasured check is never a pass or a fail. A status the harness wrote into the journal is kept as written. ## The export payload - `quality_metric` is `"checks"`. - `candidates` holds one candidate: the system under test at one version, named by `--label`. - Each candidate item is one case and carries its `checks`, each with `name`, `status`, `evidence`, and `ruled`. - Each item carries `harness_status`: `PASS`, `FAIL`, `PARTIAL`, `BLOCKED`, or `ERROR`. Quality is 1.0 for `PASS`, 0.0 for `FAIL`, and null for the rest. - The candidate's `source_revision` is `"@"`, read from `meta.json`. ## Push ``` redcrown login redcrown push [--experiment ] [--no-receipts] [--proof-link] ``` Push the first run with no `--experiment`. The output line is `pushed run (experiment )`. Pass that experiment id with `--experiment` on every later push, so the runs share one experiment. Where the record lands: the run appears in the app under **History**. Its report view lists every case with its checks, worst first, and compares the run with the earlier run of the same experiment, check by check. `--proof-link` mints a public page and prints `proof link: https://app.redcrown.ai/proof/`. A run with an `ERROR` case is pushed, but the proof link is refused by the publish gate and the output quotes the report's own caveat. A `BLOCKED` or `PARTIAL` case is disclosed on the page, not refused. Do not pass `--publish-anyway` unless the owner asked for it. Outputs and evidence lines reach the record. Keep private content out of `evidence`, or push with `--no-receipts`. ## Never claim When you report a result, in a commit message, a pull request, a summary, or a message to the owner: - Do not call a result verified. Say "graded against the rules the owner stated". - Do not describe RedCrown as a monitor or as a watcher of the product. It reads the journal when you run a command. - Do not say RedCrown knows the reason for a failure. It records which check failed and the evidence line. - Do not say an expert checked the result. A reviewer verdict exists only when a reviewer cast one through the reviewer portal. - Say "compared with the last run" for a compare, and quote the `regressed`, `fixed`, `inconclusive`, and `newly measured` counts as printed. - Do not turn an unmeasured check or a `BLOCKED` case into a pass rate. Quote both denominators as the report prints them. Last verified 2026-09-23.