Fix invalid JSON Schema for query_results_cache_retrieve

[Copilot]

Closes #262.

Reported Bug

GitHub Copilot Chat rejects the ql-mcp server with HTTP 400 "[...] is not of type 'object', 'boolean'" because query_results_cache_retrieve exposes lineRange and resultIndices as z.tuple([...]), which zod-to-json-schema serializes to an array-style schema (items: [{...}, {...}]) that strict JSON-Schema validators reject.

Update Metadata

• Breaking Changes: Yes — wire-level shape of lineRange / resultIndices changes from [start, end] to { start, end }. The tool was effectively unusable from Copilot Chat before, so the blast radius is small.
• API Compatibility: Changed (input shape only; behavior preserved)
• Performance Impact: Neutral

🎯 Changes Description

Current Behavior

lineRange / resultIndices are declared with z.tuple([...]). The MCP SDK serializes the tool's input schema via zod-to-json-schema, producing per-property values that are JSON arrays. OpenAI/Copilot's strict validator requires every property's schema value to be an object or boolean, and refuses to load the server.

Updated Behavior

Both parameters are declared with z.object({ start, end }) (same min / start <= end refinements) and converted back to [start, end] tuples at the call boundary, so SqliteStore is unchanged. Resulting JSON Schema is a clean type: "object" with start / end integer properties — accepted by Copilot Chat.

Motivation

Restore usability of the entire ql-mcp server in GitHub Copilot Chat, where a single malformed property schema currently fails the whole tools/list validation.

🔄 Before vs. After Comparison

API Changes

// BEFORE
lineRange: z.tuple([z.number().int().min(1), z.number().int().min(1)])
  .refine(([s, e]) => s <= e, { message: 'lineRange start must be <= end' })
  .optional(),

// AFTER
lineRange: z.object({
  start: z.number().int().min(1),
  end:   z.number().int().min(1),
})
  .refine(({ start, end }) => start <= end, { message: 'lineRange.start must be <= lineRange.end' })
  .optional(),

Output Format Changes

Tool output is unchanged. The wire-level input for the affected parameters changes shape:

// BEFORE
{ "cacheKey": "...", "lineRange": [1, 10], "resultIndices": [0, 5] }

// AFTER
{ "cacheKey": "...", "lineRange": { "start": 1, "end": 10 }, "resultIndices": { "start": 0, "end": 5 } }

The serialized JSON Schema for lineRange is now:

{
  "type": "object",
  "properties": {
    "start": { "type": "integer", "minimum": 1 },
    "end":   { "type": "integer", "minimum": 1 }
  },
  "required": ["start", "end"],
  "additionalProperties": false
}

Validation Scenarios

1. Schema serialization: Asserts every property of every cache tool's inputSchema is an object/boolean (never an array) using the SDK's real toJsonSchemaCompat.
2. Wire-protocol: New extension e2e test calls client.listTools() against a spawned server and enforces the same invariant for every registered tool, then invokes query_results_cache_retrieve with { start, end }.
3. Validation: Object form accepted; legacy [start, end] tuple rejected; start > end, negatives, and floats rejected.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[Copilot]

Pull request overview

This PR fixes a JSON Schema incompatibility that caused GitHub Copilot Chat to reject the MCP server (HTTP 400 ... is not of type 'object', 'boolean') by changing query_results_cache_retrieve input parameters from tuple-form Zod schemas to object-form schemas that serialize cleanly via zod-to-json-schema.

Changes:

• Replace lineRange / resultIndices input types from z.tuple([start,end]) to z.object({ start, end }) and adapt the handler by converting back to tuples at the store boundary.
• Add/expand regression tests to ensure tool input schemas never contain array-valued JSON Schema nodes (unit-level and VS Code e2e).
• Update the client integration-test fixture inputs and document the breaking input-shape change in CHANGELOG.md.

Show a summary per file

File	Description
server/src/tools/cache-tools.ts	Changes query_results_cache_retrieve schema for lineRange/resultIndices to object form; converts to tuple internally for existing store APIs.
server/test/src/tools/cache-tools.test.ts	Updates schema validation tests for new object shape and adds JSON-schema serialization regression coverage for cache tools.
server/test/src/tools/tool-schema-validation.test.ts	Adds a new cross-tool regression test ensuring strict JSON Schema compatibility across all tool input schemas.
extensions/vscode/test/suite/mcp-tool-e2e.integration.test.ts	Adds wire-protocol regression coverage ensuring listed tool schemas are strict-validator compatible and exercises new argument shape.
client/integration-tests/.../test-config.json	Updates fixture to pass lineRange as {start,end}.
client/integration-tests/.../before/monitoring-state.json	Updates stored parameters snapshot to the new {start,end} shape.
client/integration-tests/.../after/monitoring-state.json	Updates expected parameters snapshot to the new {start,end} shape.
CHANGELOG.md	Documents the Copilot Chat HTTP 400 schema issue and the breaking input-shape change under [Unreleased].
server/dist/codeql-development-mcp-server.js	Rebuilt bundled artifact reflecting the schema and handler changes.

Copilot's findings

• Files reviewed: 8/10 changed files
• Comments generated: 2

[Copilot]

Pull request overview

Fixes Copilot Chat compatibility by changing query_results_cache_retrieve’s lineRange / resultIndices input shape from Zod tuples (which serialize to array-valued schemas) to { start, end } objects, and adds regression tests to ensure all tool schemas remain strict-JSON-Schema-compatible.

Changes:

• Update query_results_cache_retrieve inputs to object ranges and adapt handler to pass tuples to the underlying store.
• Add unit/e2e regression tests to ensure tool input schemas never contain array-valued schema nodes (Copilot/OpenAI strict validation).
• Document the change in the root changelog and update client integration test fixtures to use the new input shape.

Show a summary per file

File	Description
server/src/tools/cache-tools.ts	Switch lineRange / resultIndices from z.tuple to z.object({ start, end }) and convert back to tuple at the store boundary.
server/test/src/tools/cache-tools.test.ts	Update schema validation tests for new object-form inputs and add JSON Schema serialization regression tests for cache tools.
server/test/src/tools/tool-schema-validation.test.ts	New global tool-schema regression test validating that tool schemas don’t contain array-valued schema nodes.
extensions/vscode/test/suite/mcp-tool-e2e.integration.test.ts	Add wire-level regression test that listTools() returns strict-JSON-Schema-compatible inputSchema for every tool, and exercise new object-form args.
client/integration-tests/primitives/tools/query_results_cache_retrieve/retrieve_with_subset/test-config.json	Update integration test tool arguments to include object-form lineRange.
client/integration-tests/primitives/tools/query_results_cache_retrieve/retrieve_with_subset/before/monitoring-state.json	Update recorded parameters to include object-form lineRange.
client/integration-tests/primitives/tools/query_results_cache_retrieve/retrieve_with_subset/after/monitoring-state.json	Update recorded parameters to include object-form lineRange.
CHANGELOG.md	Add an Unreleased entry describing the schema fix and input shape change.
server/dist/codeql-development-mcp-server.js	Bundled output reflecting the TypeScript changes.

Copilot's findings

• Files reviewed: 8/10 changed files
• Comments generated: 2

[Copilot]

Pull request overview

This PR fixes a Copilot Chat compatibility issue by changing query_results_cache_retrieve input parameters from tuple form ([start, end]) to object form ({ start, end }), avoiding invalid JSON Schema serialization that caused tools/list to be rejected.

Changes:

• Update query_results_cache_retrieve input schema for lineRange and resultIndices from z.tuple(...) to z.object({ start, end }), converting back to tuples at the store boundary.
• Add regression tests to ensure tool input schemas never serialize to array-valued JSON Schema fragments (unit + VS Code e2e).
• Update client integration test fixtures and changelog to reflect the new wire-level input shape.

Show a summary per file

File	Description
server/src/tools/cache-tools.ts	Switch lineRange/resultIndices to object inputs and convert back to tuple internally to keep store APIs unchanged.
server/test/src/tools/cache-tools.test.ts	Update schema validation expectations and add cache-tool JSON Schema serialization regression tests.
server/test/src/tools/tool-schema-validation.test.ts	New test validating JSON Schema serialization invariants across all registered tools.
extensions/vscode/test/suite/mcp-tool-e2e.integration.test.ts	Add wire-level e2e regression asserting all tool schemas are strict-JSON-Schema-valid and validate the new {start,end} inputs.
client/integration-tests/**/test-config.json	Update tool invocation arguments to use the new lineRange object form.
client/integration-tests/**/monitoring-state.json	Update stored parameters snapshots to match the new input shape.
CHANGELOG.md	Document the fix and breaking input-shape change under [Unreleased].
server/dist/codeql-development-mcp-server.js	Regenerated bundle reflecting the schema and handler updates.

Copilot's findings

• Files reviewed: 8/10 changed files
• Comments generated: 0