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

Annotations already declare readOnlyHint=false and destructiveHint=true, and the description does not contradict them. However, it never explains why the operation is flagged destructive (e.g., whether an existing pin position is overwritten, or what happens to anchored comments) and does not mention the project-scoping refusal behavior. It adds the 'free pin' nuance but little else beyond annotations.

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?

Two short sentences, front-loaded with the action and coordinates, then the use case. Nothing is wasted and nothing is buried.

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?

For a four-parameter mutation with no output schema, the description plus the richly documented schema cover the call adequately. Minor gap: no indication of what the response contains or subsequent effects on the thread.

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 100%, with all four parameters documented including threadId's UUID format and expectedProjectId's access-refusal semantics. The description restates pinX/pinY only and adds no meaning beyond the schema, so the baseline 3 applies.

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?

States a specific verb ('Moves') and resource ('a comment pin') plus the effect (to a new canvas position), with the relevant params named inline. It is clearly distinguishable from siblings like move_cell, move_content_block, resolve_comment, and delete_comment, though it does not explicitly call out those distinctions.

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?

Provides a concrete usage context: repositioning a 'free' pin after a layout change. That tells the agent when the tool is appropriate, but gives no exclusions or alternative tools for anchored/non-free pins.

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