fix(pull_request_read): expose 'after' cursor parameter in input schema#2489
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SamMorrowDrums merged 2 commits intoMay 19, 2026
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The `pull_request_read` tool description tells clients that `get_review_comments` uses cursor-based pagination (`perPage`, `after`), and the handler does plumb `after` through to the GraphQL query, but the input schema only declared `page` and `perPage` (via `WithPagination`). Because `after` was not advertised in `inputSchema`, MCP clients had no way to request it, leaving cursor pagination effectively broken: `perPage: 1` returned only the first thread with no way to advance, and `page` was silently ignored by the GraphQL path. This change adds `after` to the schema (string, optional) with a description making clear it only applies to `get_review_comments`. All other methods continue to ignore it. No handler behavior is changed. - Add `after` schema property after `WithPagination` in `PullRequestRead` - Regenerate `__toolsnaps__/pull_request_read.snap` and update README - Add a regression test asserting `after` is in the schema and a new table-driven case verifying the cursor is forwarded to the GraphQL query Fixes github#2122 (for the `get_review_comments` pagination part). The remaining concerns in github#2122 about unbounded response sizes for `get`, `get_diff`, and `get_reviews` are deferred to follow-up design.
SamMorrowDrums
approved these changes
May 19, 2026
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What
The
pull_request_readtool advertises in both its description and the documentation that theget_review_commentsmethod uses cursor-based pagination (perPage,after), and the handler does plumbafterthrough to the GraphQL query. But the tool'sinputSchemaonly declaredpageandperPage(viaWithPagination) —afterwas never exposed.As a result, MCP clients had no way to request the
aftercursor, leaving cursor pagination effectively broken:perPage: 1returned only the first thread with no way to advancepage: 2, 3, ...was silently ignored by the GraphQL pathperPage, which risks the unbounded-payload problem also tracked inpull_request_readmethods return unbounded payloads that crash IDE clients;get_review_commentspagination is broken (afterparam missing from schema) #2122This PR is a small, surgical fix for the schema bug.
Changes
pkg/github/pullrequests.go: After the existingWithPagination(schema)call inPullRequestRead, add anafterproperty (string, optional) to the schema with a description making clear it only applies toget_review_comments. All other methods continue to ignore it. No handler behavior is changed.pkg/github/__toolsnaps__/pull_request_read.snap: Regenerated viaUPDATE_TOOLSNAPS=true go test ./pkg/github.README.md: Regenerated viago run ./cmd/github-mcp-server generate-docs.pkg/github/pullrequests_test.go: Augment the schema-verification block inTest_GetPullRequestCommentsto assertafteris present (regression guard) and add a new table-driven case"after cursor is forwarded to GraphQL query"that verifies the cursor flows fromrequestArgs["after"]into the GraphQL variables.Validation
golangci-lintis not installed locally; CI will runscript/lint.The new test case provides explicit coverage: the GraphQL mock matcher expects
"after": githubv4.String("cursor-page-2")and the test passes"after": "cursor-page-2"inrequestArgs, so a regression that dropsafterfrom the schema or handler wiring would fail this test.Scope note
This PR only addresses the missing-
afterportion of #2122. The remaining concerns in that issue — unbounded payloads fromget,get_diff, andget_reviews— involve more invasive API surface choices (field-selection parameters, truncation, etc.) and are better handled in a follow-up after design discussion. Happy to take that on as a separate PR if maintainers prefer a particular approach.Fixes #2122 (partial)