pin_file

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

The description contradicts the annotation readOnlyHint=true. The description indicates a write operation (setting a weight, creating a pin), but readOnlyHint suggests no side effects. This is a serious inconsistency. The description also mentions a cap and return format, but does not disclose other behavioral details like error handling or permissions.

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 two sentences plus a note on cap and return. It is front-loaded with the primary action, followed by usage guidance and limits. Every sentence adds value with no redundancy.

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?

The description covers purpose, usage, parameters (via schema), cap, and return format (no output schema, but description gives { ok, pin? }). It lacks error handling or prerequisites, but given the annotations (idempotent, not destructive), the description is fairly complete.

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 coverage is 100% with descriptions for all three parameters. The description adds value by noting the cap of 50 active pins, the return JSON format, and context on use cases. This goes beyond the schema, justifying a score above baseline 3.

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 boosts/demotes a file in PageRank-driven ranking by setting a multiplicative weight. It distinguishes from siblings like pin_symbol (which pins a symbol) and unpin (which removes pins). Use cases are specific: surface canonical examples, architectural keystones, or files central to a feature.

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 explicitly says 'Use to surface canonical examples, architectural keystones, or files central to a work-in-progress feature.' It also mentions a cap of 50 active pins per project. However, it does not explicitly state when not to use or compare to alternatives like pin_symbol or unpin.

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