Add pagination support toget_pull_request_files tool

Fixes#527

Problem

Theget_pull_request_files tool currently retrieves only the first 30 files with diffs of any PR that contains more than 30 files. This is a limitation because large PRs with many files cannot be fully analyzed.

Solution

Added pagination support to theget_pull_request_files tool by:

• AddingWithPagination() to the tool definition
• UsingOptionalPaginationParams(request) to handlepage andperPage parameters
• Passing pagination parameters to the GitHub APIListFiles call
• Following the same pattern used by other paginated tools in the codebase

Changes Made

1. Core Implementation (pkg/github/pullrequests.go)

// Added WithPagination() to tool definitionWithPagination(),// Added pagination parameter handlingpagination,err:=OptionalPaginationParams(request)iferr!=nil {returnmcp.NewToolResultError(err.Error()),nil}// Updated GitHub API call to use paginationopts:=&github.ListOptions{PerPage:pagination.perPage,Page:pagination.page,}

2. Test Updates (pkg/github/pullrequests_test.go)

• Added verification that pagination parameters (page,perPage) are present in tool schema
• Added test case for successful files fetch with pagination parameters
• Updated tool schema snapshot to reflect new parameters

3. Schema Snapshot (pkg/github/__toolsnaps__/get_pull_request_files.snap)

• Automatically updated to include new pagination parameters
• Ensures schema changes are tracked and validated

Testing Done

1. Unit Tests

# All tests passgotest ./pkg/github -v

Test Results:

• ✅Test_GetPullRequestFiles - All test cases pass including new pagination test
• ✅ Schema verification - Confirmspage andperPage parameters are present
• ✅ Pagination functionality - Verifies tool works with pagination parameters

2. Integration Testing

# Verified tool schema includes pagination parametersGITHUB_PERSONAL_ACCESS_TOKEN=xxx ./mcpcurl --stdio-server-cmd="./github-mcp-server stdio --toolsets pull_requests" schema

Schema Verification:

{"name":"get_pull_request_files","inputSchema": {"properties": {"owner": {"description":"Repository owner","type":"string"},"page": {"description":"Page number for pagination (min 1)","minimum":1,"type":"number"},"perPage": {"description":"Results per page for pagination (min 1, max 100)","maximum":100,"minimum":1,"type":"number"},"pullNumber": {"description":"Pull request number","type":"number"},"repo": {"description":"Repository name","type":"string"}    },"required": ["owner","repo","pullNumber"]  }}

3. GitHub API Verification

# Verified GitHub API supports pagination for PR filescurl -H"Authorization: token xxx""https://api.github.com/repos/github/github-mcp-server/pulls/521/files?per_page=2&page=1"

API Response: Successfully returned paginated results with 2 files per page.

4. Build Verification

# Server builds successfully with changesgo build -o github-mcp-server cmd/github-mcp-server/main.go

Usage Examples

Default behavior (no pagination parameters):

{"owner":"github","repo":"github-mcp-server","pullNumber":123}

With pagination:

{"owner":"github","repo":"github-mcp-server","pullNumber":123,"page":2,"perPage":10}

Backward Compatibility

• ✅Fully backward compatible - Existing calls without pagination parameters work exactly as before
• ✅Optional parameters -page andperPage are optional with sensible defaults
• ✅Same response format - Returns the same JSON structure as before

Impact

• Large PRs: Can now analyze PRs with more than 30 files
• Performance: Users can control the number of files retrieved per request
• Flexibility: Supports both default behavior and custom pagination

Files Changed

• pkg/github/pullrequests.go - Core implementation
• pkg/github/pullrequests_test.go - Test updates
• pkg/github/__toolsnaps__/get_pull_request_files.snap - Schema snapshot