Cost Estimate

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

Description adds key behavioral traits beyond annotations: it does not invoke endpoints, returns breakdown with tier annotations, and has a 5-minute cache TTL. No contradiction with 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?

Very concise: three sentences covering purpose, output, usage guidance, and caching. Front-loaded with key information, no wasted words.

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 1-parameter tool with no output schema, the description fully explains input, behavior, output, caching, and usage context. All relevant details are present.

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?

With 100% schema coverage, baseline is 3. The description adds context about credit estimation but no extra parameter details beyond schema's already clear definition.

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 clearly states the tool estimates credit cost of endpoints without invoking them, and distinguishes from actual endpoint invocation. It specifies returns total + per-endpoint breakdown.

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 explicit when-to-use guidance: 'planning multi-step workflows: estimate first, ask user confirmation, then invoke.' Does not mention alternatives or exclusions, but clear context.

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