stacklok / toolhive / 19077779662

51%

Build Type

push

github

Committed by web-flow

Commit Message

Fix vmcp tool schema double-nesting bug (#2456)

The vmcp server was incorrectly wrapping tool InputSchema (which is
already a complete JSON Schema with type, properties, and required
fields) in an additional ToolInputSchema struct, causing invalid
double-nesting.

This resulted in schemas like:
{
  "type": "object",
  "properties": {
    "properties": {...},
    "required": [...],
    "type": "object"
  }
}

Instead of the correct:
{
  "type": "object",
  "properties": {...},
  "required": [...]
}

VSCode and other strict MCP clients reject these malformed schemas with
validation errors like "Incorrect type. Expected one of object, boolean
(at /properties/required)".

The fix uses RawInputSchema to marshal the complete schema as-is,
avoiding the double-nesting issue. Added comprehensive tests to verify
the fix and prevent regression.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude <noreply@anthropic.com>

Run Details

10 of 10 new or added lines in 1 file covered. (100.0%)

6 existing lines in 2 files now uncovered.

21779 of 45170 relevant lines covered (48.22%)

37.46 hits per line