The missing_tool safe output required both tool and reason parameters, preventing agents from reporting general limitations without naming a specific tool. The MCP server validation rejected calls missing the tool parameter.

Changes

Schema updates (safe_outputs_tools.json, agent-output.json):

• Changed required: ["tool", "reason"] → required: ["reason"]
• Tool parameter now optional, marked "Optional:" in description

Handler updates (missing_tool.cjs):

• Removed validation rejecting missing tool field
• Handler accepts null tool values
• Conditional logging based on tool presence

Type definitions (safe-outputs.d.ts):

• Changed tool: string → tool?: string

Usage

// Specific tool (existing behavior)
{ tool: "docker", reason: "Need containerization", alternatives: "Use VM" }

// General limitation (now supported)
{ reason: "Cannot access external APIs", alternatives: "Manual data input" }

All existing tests pass. Added test coverage for optional tool parameter.

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