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

Goes well beyond the annotations (readOnlyHint=false, openWorldHint=false, idempotentHint=false, destructiveHint=false) by disclosing that a human reads it, that there is no payment or account requirement, and that throughput is rate-limited to a few messages per hour. The 'no secrets or private data' caveat is also useful guidance the annotations do not convey.

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 short sentences, front-loaded with the cost/effort answer ('Free.') that a caller cares about first. Every clause carries information: purpose, examples, human review, cost/auth, rate limit.

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 simple four-parameter write tool with no output schema, the description supplies everything needed to call it correctly — purpose, cost, auth, throughput limit, and content cautions. No material gap remains.

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 75%, so the schema already documents route, contact, and message. The description's mention of 'a bug, an idea or a thanks' loosely maps to the kind enum but adds no new meaning for route or contact, so 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 action (tell the service operators what worked/failed/is missed) and enumerates the input kinds (bug, idea, thanks), which maps directly onto the tool's role. It is unmistakably distinct from the fetch and proxy siblings.

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?

Clearly signals when to use it — for bugs, ideas, or thanks — and gives concrete operational context (free, no account needed, a few messages per hour). It stops short of an explicit when-not or a named alternative, but for a terminal feedback action that is a minor omission.

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