> ## Documentation Index > Fetch the complete documentation index at: https://docs.patch.gg/llms.txt > Use this file to discover all available pages before exploring further. # What a change request changes > Its commits and changed files, with each text file's patch, compared to where its branch left the branch it's for, or for a merged request, to what it merged onto. `up_to_date` says whether it can merge as it is. ## OpenAPI ````yaml /api-reference/openapi.json get /projects/{owner}/{slug}/change-requests/{number}/diff openapi: 3.1.0 info: title: Patch API version: 1.0.0 description: >- The public API behind patch.gg, the desktop app and pch. Changes within v1 are additive only. Errors are { error: { code, message, details } }; branch on code. servers: - url: https://patch.gg/api/v1 security: [] paths: /projects/{owner}/{slug}/change-requests/{number}/diff: get: tags: - Change requests summary: What a change request changes description: >- Its commits and changed files, with each text file's patch, compared to where its branch left the branch it's for, or for a merged request, to what it merged onto. `up_to_date` says whether it can merge as it is. parameters: - schema: type: string example: patch required: true name: owner in: path - schema: type: string example: demo-mod required: true name: slug in: path - schema: type: integer minimum: 1 example: 12 required: true name: number in: path responses: '200': description: What it changes content: application/json: schema: $ref: '#/components/schemas/ChangeRequestDiff' '308': description: Renamed; follow the Location header '400': description: Invalid request content: application/json: schema: $ref: '#/components/schemas/Error' '401': description: Not signed in content: application/json: schema: $ref: '#/components/schemas/Error' '403': description: Not allowed content: application/json: schema: $ref: '#/components/schemas/Error' '404': description: Not found content: application/json: schema: $ref: '#/components/schemas/Error' '429': description: >- Too many requests: wait as long as `Retry-After` says (`retry_after_s` in `details`), then retry content: application/json: schema: $ref: '#/components/schemas/Error' '502': description: The repo couldn't be read content: application/json: schema: $ref: '#/components/schemas/Error' '503': description: Change requests aren't set up here, or the repo is waking up content: application/json: schema: $ref: '#/components/schemas/Error' components: schemas: ChangeRequestDiff: type: object properties: base: type: - string - 'null' description: >- The commit its changes are compared to: where its branch left the branch it's for, or for a merged request, what it merged onto. Null when there's no shared history to compare, or the branch is gone. head: type: string description: Its latest commit. branch_head: type: - string - 'null' description: >- The latest commit of the branch it's for. Null for a merged request, or when the branch is gone. up_to_date: type: - boolean - 'null' description: >- Whether it can merge as it is: the branch it's for hasn't moved on since its branch left. Null for a request that isn't open. commit_count: type: integer description: 'How many commits it brings: when `truncated`, at least this many.' commits: type: array items: type: object properties: id: type: string subject: type: string description: Its message's first line author: type: string committed_at: type: string format: date-time required: - id - subject - author - committed_at description: 'Its commits, newest first: the first 250.' files: type: array items: type: object properties: path: type: string old_path: type: - string - 'null' description: Where it was, when it moved. status: type: string enum: - added - modified - deleted - renamed type: type: string enum: - blob - exec - symlink - gitlink old_blob: type: - string - 'null' description: >- Its git object before, shortened. For a submodule, the whole commit. blob: type: - string - 'null' description: >- Its git object after, shortened. For a submodule, the whole commit. additions: type: integer description: Lines added, when it has a patch. deletions: type: integer description: Lines removed, when it has a patch. patch: type: - string - 'null' description: >- Its changed lines, in the hunks `git diff` shows, with 3 lines around them. Bytes that aren't UTF-8 show as U+FFFD, so a patch with any won't apply. no_patch: type: - string - 'null' enum: - binary - big_file - too_big - too_much - null description: >- Why a file whose contents changed has no patch. binary: it isn't text. big_file: it's in Git LFS. too_big: its patch is over 1 MiB, or couldn't be read. too_much: the diff is too long to show it. big_file: type: - object - 'null' properties: old: type: - object - 'null' properties: sha256: type: string size: type: integer required: - sha256 - size new: type: - object - 'null' properties: sha256: type: string size: type: integer required: - sha256 - size required: - old - new description: The Git LFS files it points at, before and after. required: - path - old_path - status - type - old_blob - blob - additions - deletions - patch - no_patch - big_file truncated: type: boolean description: >- Whether anything was left out: patches stop at 300 files or 2 MiB, the list of files at 3,000, and commits near 800. A change too big to read at all has no files. required: - base - head - branch_head - up_to_date - commit_count - commits - files - truncated Error: type: object properties: error: type: object properties: code: type: string example: version_exists message: type: string details: {} required: - code - message required: - error ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.