list_badges

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description does not need to restate safety. It adds that the tool returns a count (badges count), which is behavioral context beyond the annotations. However, it does not describe the response format, potential errors, or whether the count is global or user-specific. With annotations covering safety, a 3 is appropriate – the description adds minimal but useful behavioral detail.

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 exceptionally concise: two short sentences with no filler. The purpose is front-loaded ('Get badges count'), and the endpoint is included as a useful technical detail. Every word earns its place – there is no redundancy or vague language.

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 tool with no parameters, a simple output (badges count), and annotations covering safety, the description is complete. The output schema exists (indicated by 'has output schema: true'), so the description need not explain the return structure. The only minor gap is the lack of clarification about what 'badges' refers to, but this is a domain-specific detail that likely falls outside the tool's responsibility.

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 has zero parameters, so the schema fully covers parameters (100% coverage). With no parameters to document, the baseline is 4. The description does not need to add parameter information, and it correctly includes the HTTP endpoint (GET /api/badges) which is not part of the schema but adds clarity about the operation.

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 clear verb and resource: 'Get badges count' – it identifies exactly what the tool does. However, it doesn't clarify what 'badges' represent (e.g., notification badges, achievement badges), which is a minor ambiguity. It distinguishes from sibling tools by resource (badges vs. movies, episodes, etc.), so it is not confused with other list_* tools.

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 phrase 'to update the UI' provides a clear context for when to use this tool – when the UI needs to display a badge count. It does not explicitly mention alternatives or exclusions, but given there are no similar badge tools among the siblings, the usage context is sufficient. The guidance is clear and directly actionable.

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