Command Runner Reference

Reference for executing development commands and parsing output into structured, actionable summaries.

Runtime Detection

Before running ANY command, detect the correct runtime:

Detection Priority

1. Agentuity project (highest priority):

   • If agentuity.json or .agentuity/ exists → bun
   • Agentuity projects are ALWAYS bun-only

2. JavaScript/TypeScript lockfiles:

   • bun.lockb → bun
   • package-lock.json → npm
   • pnpm-lock.yaml → pnpm
   • yarn.lock → yarn

3. Other ecosystems:

   • go.mod → go
   • Cargo.toml → cargo (Rust)
   • pyproject.toml → uv or poetry
   • requirements.txt → pip

Command Patterns by Ecosystem

JavaScript/TypeScript (bun/npm/pnpm/yarn)

Go

Rust (cargo)

Output Parsing Intelligence

Error Extraction Rules

1. Deduplicate — Same error in multiple files? Report once with count
2. Prioritize — Errors before warnings
3. Truncate — Top 10 issues max (note if more exist)
4. Extract locations — file:line format when available
5. Classify — type error, syntax error, lint error, test failure

Error Classification

Location Extraction

Extract file:line from common formats:

• TypeScript: src/foo.ts(10,5): error TS2322
• ESLint: src/foo.ts:10:5 error
• Go: ./pkg/foo.go:10:5:
• Rust: --> src/main.rs:10:5
• Python: File "src/foo.py", line 10

Structured Output Format

## [Task] Result: [PASSED | FAILED | WARNINGS]

**Runtime:** [bun | npm | pnpm | go | cargo | uv]
**Command:** `[exact command executed]`
**Duration:** [time in seconds]
**Exit Code:** [0 | non-zero]

### Errors ([count])

| File         | Line | Type | Message                                          |
| ------------ | ---- | ---- | ------------------------------------------------ |
| `src/foo.ts` | 45   | Type | Type 'string' is not assignable to type 'number' |

### Warnings ([count])

| File         | Line | Message           |
| ------------ | ---- | ----------------- |
| `src/baz.ts` | 8    | Unused import 'y' |

### Summary

[One sentence: what happened, what the calling agent should know]

Execution Workflow

1. Detect Runtime — Check for agentuity.json, then lockfiles
2. Discover or Use Explicit Command — Auto-discover from package.json or use provided command
3. Execute Command — Capture stdout, stderr, exit code, duration
4. Parse Output — Extract and classify errors/warnings with file:line
5. Return Structured Result — Format using the template above