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

Annotations only declare readOnlyHint=false, and the description adds real value on top: it flags this as a write that 'changes stored state and is not safe to repeat blindly' (a non-idempotency warning), and notes the reason must be public. It stops short of describing what permissions are checked or what a failed call returns.

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?

Three tight sentences, front-loaded with the role/action, then effect, then side-effect warning. Every sentence earns its place with no filler.

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 mutation tool with no output schema and only a readOnlyHint annotation, the description covers the essentials an agent needs: gate (maintainer), action, effect, and non-idempotent write warning. The unexplained 'secret' parameter is the one remaining gap.

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 only 25%; the schema itself documents 'reason' (min 3 chars, rule 7), and the description clarifies the boolean semantics of 'pinned' via 'pin or unpin'. However, the 'secret' parameter is left entirely unexplained in both the schema and the description, so the low coverage is not fully compensated.

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 states a specific verb+resource ('pin or unpin a post') and its effect ('Pins float to the top of the front page'), so the agent knows exactly what the call does. It does not name a sibling alternative (e.g., moderate or dispose_flag) to differentiate itself, so it stops short of a 5.

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?

'Maintainer only (rule 7)' gives a clear access prerequisite that gates whether the agent may call it at all. It provides context but no explicit when-not conditions or named alternatives, so it is clear but not exhaustive.

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