fix(server): work around Claude Desktop JSON Schema dialect rejection - #42
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antonisobkowicz-asana merged 2 commits intoSep 8, 2026
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…patibility @modelcontextprotocol/sdk (1.30.0, latest) always advertises tool schemas with $schema: draft-07, since its tools/list handler never passes a target to the schema converter. Claude Desktop's tool runner only accepts JSON Schema 2020-12 and rejects every call as a result. Wrap the transport's send to relabel the dialect in transit until the upstream fix (modelcontextprotocol/typescript-sdk#2084, #2721) lands in a release; safe here since this server never emits tuple-style items arrays, the one keyword that differs between the two dialects. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
This test runs install.sh three times in a row (fresh install, upgrade, no-op rerun), which was intermittently exceeding vitest's default 5s timeout on a loaded machine. No other installer test invokes the script more than twice. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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## Summary - Bumps `package.json`/`package-lock.json` to 0.4.1 to release the Claude Desktop JSON Schema dialect workaround (#42). ## Test plan - [x] `npm ci` - [x] `npm run check` (typecheck, lint, 380 tests, build) — all passing - [x] `npm audit` — 0 vulnerabilities - [x] `npm pack --dry-run` — tarball contents look correct 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
get_context,search_tickets,list_workspaces, ...) because@modelcontextprotocol/sdk(1.30.0, latest) always advertisestools/listschemas with$schema: draft-07— its handler never passes atargetto the schema converter. Claude Desktop's tool runner only accepts JSON Schema 2020-12.modelcontextprotocol/typescript-sdk#2084and#2721, both open; proposed fixes#2085/#2653not yet merged/released).applyJsonSchemaDialectWorkaround, which wraps the transport'ssendto relabel the declared dialect from draft-07 to 2020-12 in transit, wired intocli.tsright beforeserver.connect(). Safe here because this server never emits tuple-styleitemsarrays — the one keyword whose meaning differs between the two dialects. Marked with aTODOto delete once a released SDK version fixes this upstream.install.shthree times end-to-end (fresh install, upgrade, no-op rerun) — it was intermittently exceeding vitest's default 5s timeout on a loaded machine.Test plan
npx tsc --noEmitnpm run lintnpx vitest run— 380 tests passing, including new coverage for the workaround (dialect relabeling, non-tools/list messages passed through untouched, wiring throughrunCli)🤖 Generated with Claude Code