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

Annotations already declare readOnlyHint=true, destructiveHint=false and a closed-world scope, so safety is covered. The description adds real context beyond that: the result is one entry per checked app, each carrying a status, and the listed check_id is the key needed for follow-up calls. It does not discuss completeness of the list, which is a minor gap for an unpaginated read.

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, each earning its place: what is returned, when to call it, and where to go next for details. The core listing behavior is front-loaded in the first sentence.

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 zero-parameter read tool with an output schema and rich annotations, the description supplies everything needed to select and invoke it: scope, return granularity, and routing to the sibling that reads a single result. No gaps remain that the structured fields do not already cover.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline is 4. It correctly avoids inventing filter options that the schema does not support.

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 and resource ('List the signed-in person's VibeFix checks') and clarifies the name/title mismatch by explaining a check maps to 'one per app checked', including that status is returned. An agent can distinguish it from get_check_result without opening either schema.

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?

Explicit trigger ('Call this when they ask which of their apps VibeFix has checked') plus a named alternative with the condition that selects it ('To read a check's result, call get_check_result with its check_id'). Nothing is left to inference.

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