intact: Reliable File Edits for Agents

intact keeps a small amount of drift from turning a precise file change into a failed edit. Its seven-rung reconciliation ladder re-finds a uniquely identifiable block, reports the tolerance it needed, and refuses ambiguous matches instead of guessing. Use it as a Python library, the tact CLI, or an MCP server.

Get a safe edit through

Start with the tutorial if you want to see the complete read, edit, and undo cycle. The reference is the map of every CLI command, MCP tool, and library entry point.

Core guidance

• Tutorial: make one resilient edit
  • 1. Install and create a file
  • 2. Read before you edit
  • 3. Simulate harmless drift
  • 4. Edit and inspect the result
  • 5. Undo the write
  • Next steps
• How-to: task-oriented recipes
  • Recover a failed builtin edit
  • Apply an LLM-emitted unified diff
  • Multi-file rename via LSP
  • Anchor a block across sessions, then delta re-read
  • Fleet-native routing
  • Native-style rendering for tact tools
  • Diagnose a fleet install
  • Wire the MCP server into an agent harness
• Reference: verb ↔ CLI ↔ MCP ↔ library
  • Routing modes
  • Exit codes (CLI only)
  • MCP coverage gap
  • Deep reference
• Explanation: why tact is shaped this way
  • Drift is routine, not a permission to guess
  • A ladder preserves the strongest evidence
  • Refusal is part of the write contract
  • LSP is optional, except when identity matters
  • Convenience state is disposable
  • Provenance

API, evidence, and project records

These pages support implementation, evaluation, and maintenance. They are useful background, but are not required for a first successful edit.

Reference and records

• tact: Public API
  • Core package
  • Native hook routing
  • Installation diagnostics
  • Privacy-minimal telemetry
• Context-efficient MCP results
  • Current behavior
  • When to choose each mode
  • Dated evidence
• Public replay shape map
  • What is projected
  • Replay and safety boundary
  • Provenance, privacy, and reproduction
• tact rollout evidence report
  • Summary
  • What changed on 2026-08-03
  • Method and provenance
  • Historical: the deny window
  • Current: the ramp window
  • Test contamination of the library surface — fixed forward, unrecoverable backward
  • What this event stream cannot measure
  • Metrics this report does not cite
  • Acceptance criteria assessment
  • Ratification
  • Open measurement work
• Historical workflow report: intact 0.8.0