verify

The "did my change actually work?" tool for agents. It auto-detects how a project checks itself — typecheck / lint / test / build — runs the relevant checks, and returns structured pass/fail with parsed errors, so an agent stops re-deriving commands and grepping a wall of stdout.

verify()
→ {
    "ok": false,
    "checks": [
      { "name": "typecheck", "passed": false,
        "errors": [ { "file": "src/api.ts", "line": 42, "message": "TS2304 Cannot find name 'reqId'" } ] },
      { "name": "test", "passed": true, "duration_ms": 1840 }
    ]
  }

Why

Agents change code constantly and then flail at verifying it — re-deriving the build/test commands for every project and eyeballing raw output. verify makes "is what I just did good?" a single, structured primitive. It's the missing keystone of the loop: understand → act → verify → remember.

Tools

• verify(only?, root?, timeout_ms?) — run the detected checks; structured results. only: ["typecheck"] to run a subset.
• detect_checks(root?) — list the available checks + commands, without running.

What it detects

| Stack | Checks | |-------|--------| | Node / TS | package.json scripts (typecheck/lint/test/build) + tsc --noEmit from tsconfig | | Python | pytest, mypy, ruff/flake8 (from pyproject / setup.cfg / configs) | | Go | go build · go vet · go test | | Rust | cargo build · cargo test | | fallback | make targets |

Errors are parsed best-effort into {file, line, message} (tsc precisely; a generic file:line extractor for eslint/pytest/go/rust), with an output tail kept for anything unstructured.

Setup

npm install
npm test

Register with an MCP client:

claude mcp add verify -e VERIFY_ROOT=/path/to/project -- node /abs/path/verify/dist/server.js

Or use the CLI: agent-verify (run checks) / agent-verify detect (list them).

Honest limits

• Detection is heuristic — unusual project layouts may need the only/root args, or a package.json script it can find.
• Errors are best-effort parsed — exotic formatters fall back to the output tail.
• Runs the whole detected check (not yet diff-scoped); large suites take as long as they take (with a timeout guard).