# strata19.get_file_diff
URL: /documentation/reference/tools/get_file_diff



{/* GENERATED FILE — do not edit. Sources: src/mcp/facade/tool-projection-registry.ts (availability) + describe() in src/mcp/facade/facade-tools.ts (prose). Regenerate: pnpm exec tsx scripts/docs/site/generate-tool-reference.ts */}

## What it does [#what-it-does]

The unified diff for ONE file against a base ref, as real git diff text. Tries `<base>...HEAD`, then `<base>..HEAD`, then the uncommitted working tree. Truncation, binary files and no-change are reported as a typed `status`, never as an empty string the caller has to interpret.

## When to use it [#when-to-use-it]

**Use when:** "show me the diff for src/foo.ts" · rendering a file's hunks · inspecting one file out of a reviewed range

**Also use when:** after strata19.review\_pull\_request names a file you want to read in full

## When not to use it [#when-not-to-use-it]

you want the whole review rollup (use strata19.review\_pull\_request) or only the list of changed file names (use strata19.graph\_from\_git\_range)

## Availability [#availability]

|           |                                                        |
| --------- | ------------------------------------------------------ |
| Tier      | Expert                                                 |
| Lifecycle | Live                                                   |
| Taught by | `strata19-integrate-work`, `strata19-review-readiness` |