route

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does well. It discloses the key behavioral trait that it never executes anything, reveals the return type ('chosen' / 'candidates'), and explains the semantics of context (light file metadata, references only) and mode (overrides default). This is rich transparency beyond what the schema provides.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three sentences, front-loaded with the primary purpose, followed by behavior and parameter details. Every sentence adds value without redundancy or filler, making it highly concise and well-structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity, the presence of an output schema, and no annotations, the description is complete. It covers the purpose, execution behavior, parameter semantics, and mentions the output format. No critical information is missing for an agent to select and invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, but the description fully compensates by explaining each parameter: task is the routing query, context is optional file metadata, and mode overrides the auto/ask default. This adds meaning that the input schema alone does not provide.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's function: 'Pick the best tool or skill for `task`'. It uses a specific verb and resource, and distinguishes itself from siblings by explicitly noting it 'NEVER executes anything' and that you should invoke the pick via call_tool or use_skill.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context for when to use the tool (to pick a tool/skill) and explicitly names alternatives/next steps ('invoke the pick yourself via call_tool or use_skill'). However, it does not explicitly state when not to use it or contrast with search/admin, so the guidance is helpful but not exhaustive.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.