run

Parses test, build, and lint output into structured JSON. Only failures and summaries are returned. Passing tests are omitted.

Usage

prx run [options] <command> [args...]

Options

Flag	Description
`--raw`	Bypass parsing, return full output in JSON envelope
`--full`	Return parsed summary AND full output
`--budget N`	Token budget for output
`--timeout N`	Command timeout in seconds (default: 300)
`--plain`	Human-readable output

Examples

prx run cargo test
prx run cargo clippy
prx run pytest
prx run npm test
prx run go test ./...
prx run tsc --noEmit
prx run eslint src/

Token savings

A 164-test suite that outputs ~1,200 tokens raw becomes ~15 tokens through prx. A 304-test suite:

Method	Tokens
Raw `cargo test` output	~6,000
`prx run cargo test`	~120
Savings	98%

In a 10-iteration test-debug-fix loop on a 500-test project, prx run saves ~84,000 tokens compared to reading raw output.

Output format

All tests pass

{
  "data": {
    "exit_code": 0,
    "duration_ms": 490,
    "tool": "cargo_test",
    "summary": "164 passed, 0 failed in 0.49s",
    "passed": 164,
    "failed": 0,
    "skipped": 0,
    "failures": [],
    "warnings": [],
    "output_lines": 168,
    "output_tokens_saved": 1185
  }
}

Tests fail

{
  "data": {
    "exit_code": 1,
    "tool": "cargo_test",
    "summary": "162 passed, 2 failed in 0.52s",
    "passed": 162,
    "failed": 2,
    "failures": [
      {
        "name": "search::tests::hybrid_search",
        "location": "src/commands/search.rs:45",
        "message": "assertion `left == right` failed\n  left: 0\n right: 1"
      }
    ]
  }
}

Build/lint errors

{
  "data": {
    "exit_code": 1,
    "tool": "cargo_clippy",
    "summary": "3 warnings, 1 error",
    "failures": [
      {
        "name": "error[E0382]",
        "location": "src/main.rs:30",
        "message": "borrow of partially moved value: `cli.command`"
      }
    ],
    "warnings": [
      {
        "name": "unused_variable",
        "location": "src/output.rs:14",
        "message": "unused variable `path`"
      }
    ]
  }
}

Supported tools

Full parsing

Tool	What prx extracts
`cargo test`	Pass/fail counts, failure names, locations, assertion messages
`cargo build`	Error codes, locations, messages
`cargo clippy`	Warnings and errors with codes, locations, messages
`pytest`	Pass/fail/skip counts, failure names, locations, tracebacks
`go test`	ok/FAIL per package, failure names and messages
`jest` / `npm test`	Pass/fail/skip counts, failure names, expect/received messages
`vitest`	Pass/fail counts, failure names, diff messages
`tsc`	Error codes, file:line:col, messages
`eslint`	Warning/error counts per file, rule names
`ruff`	Lint errors with file:line
`bun test`	Pass/fail counts, failure details
`deno test`	Pass/fail counts, failure details
`dotnet test`	Pass/fail counts, failure details

Fallback

Any command not matching a known tool: exit code, last 10 lines of combined stdout+stderr, tool: "unknown".

Design principles

Never lose information on failure. When a command fails, every error and warning is in the output. Passing tests are summarized; failing tests are preserved in full.

Zero configuration. Tool detection is automatic from the command string. No config files, no flags to say “this is pytest.”

Fail-open. If a parser can’t handle the output, it falls back to raw output rather than silently dropping information.

Tips

Use prx run for every test/build/lint invocation in an agent loop. The savings compound across iterations.
The output_tokens_saved field in the response tells you exactly how many tokens were saved on that call.
Use --raw if you need the full output for debugging a parser issue.
Use --timeout for commands that might hang (e.g. integration tests with network calls).

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