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

With no annotations, the description must carry the behavioral load; it usefully discloses the per-call cost and x402 payment mechanism. It does not discuss rate limits, result pagination, or failure behavior, leaving some operational context to the schema.

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 core purpose, followed by use cases and cost. No filler or redundant restatement.

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 search tool with no output schema, the description names the key return attributes (points, comment counts, discussion links) and covers cost. Parameter details and the payment flow are adequately handled by the schema.

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 coverage is 75%, so most parameters are already documented. The description reinforces the sort values ('relevance or date') and hints at returned fields, but adds little beyond what the schema provides for q, limit, and paymentProof.

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: full-text search of Hacker News stories, including the sort modes and returned metrics. An agent can immediately identify this as the HN search tool among the broad sibling list.

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 clear use cases (tech sentiment, launch tracking) that tell the agent when this tool is relevant. It does not name explicit alternatives or when-not conditions, but no direct HN-search sibling exists.

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