v1_category_breakdown

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

With no annotations, the description fully covers behavior: it is a deterministic read from archived observations, no upstream calls, no side effects. Update frequency (~3x/day) and data source are explained. No destructive or mutable behavior is indicated.

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 relatively long but front-loaded with cost and main verb. Each sentence adds value (cost, purpose, data details, free alternative). Slightly verbose but appropriate for the level of detail.

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?

Given no output schema, the description thoroughly explains return data (services per category, catalog share, 7-day delta, taxonomy). Update frequency, cost, and free alternative are covered. For a 0-parameter read tool, this is complete.

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?

No parameters exist (0 required, schema coverage 100%), so baseline 4 applies. The description adds no parameter details, which is acceptable since there are none.

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 specifies the tool retrieves the current x402 service catalog broken down by category with 7-day deltas. It explicitly mentions the taxonomy (Agentic.Market) and data points (catalog share, delta). While sibling tool x402_market_pulse exists, the description subtly differentiates by noting a free snapshot at /v1/market-pulse, indicating alternative access.

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 description provides cost ($0.005 USDC per call) and mentions a free snapshot alternative (x402_market_pulse), guiding cost-sensitive use. It implies use for analyzing x402 supply concentration and category growth but lacks explicit when-to-use vs when-not-to-use guidance.

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