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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so safety is covered. The description adds genuinely new behavioral context: no cost, and that results include price, REST endpoint, MCP tool name, example arguments and x402 payment instructions — valuable for a catalog tool with no output schema. It stops short of disclosing result limits, pagination, or ranking behavior.

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?

Two sentences with zero filler; the free/cost signal and the search target are front-loaded, and the example list is dense with actionable query vocabulary. The return-value sentence is packed but each clause adds distinct information.

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 one-param, no-output-schema, well-annotated tool, the description covers purpose, cost, and the shape of returned data. The remaining gap is behavior when the optional query is absent (full-catalog listing vs. error) and whether results are truncated — minor but real for a catalog search.

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 100% and the single param is documented as "What you need, in a few words". The description goes beyond that by giving concrete query formulations ("honeypot", "transcribe audio", "ocr", "translate", "dns"), which teaches the agent how to phrase a capability query rather than a keyword. It does not address what happens when query is omitted.

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 (search) and resource (DevX catalog of pay-per-call agent tools) plus the search dimension (by capability). The examples ("honeypot", "transcribe audio", "ocr") make it unmistakably distinct from the concrete sibling tools like speech_to_text or translate_text, which perform work rather than discover 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 leading "Free:" signals a cost-based reason to prefer this over paid siblings, and the capability examples imply it is a discovery entry point. However, it never states when to use this versus calling a specific sibling tool directly, nor whether an empty query is valid given 0 required parameters. Usage is implied rather than prescribed.

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