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

Goes well beyond the readOnly/openWorld/non-destructive annotations by disclosing per-source result lists, partial-failure semantics (a rate-limited source reports an error without failing the whole call), and the payment model ($0.0045 USDC via x402 on specific chains). These are exactly the operational facts an agent needs before calling.

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?

Front-loads the core purpose, then behavior, params, and price in a logical order; each sentence adds real value. It is somewhat dense with payment and sample details, but nothing is clearly wasteful.

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?

No output schema exists, so the description must convey returns, and it does so at a high level ('each source returns its own list'). Combined with the annotations and full parameter documentation, this is nearly complete, though the exact return fields per source remain unspecified.

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 0% schema description coverage, the description carries the full burden and does so: query is required, sources defaults to all five values (matching the enum), and limit is constrained to 1-20 with default 5. All three parameters are given meaning beyond their bare JSON types.

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 (search developer sources) and enumerates the five concrete sources with their distinct behaviors (GitHub by stars, npm with weekly downloads, PyPI exact lookup). This clearly distinguishes it from siblings like web_search, news_search, package_check and tech_stack.

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?

Frames the tool as a one-call aggregator across developer sources, which gives clear context for when to reach for it. It stops short of explicitly naming when NOT to use it or pointing to alternatives such as package_check for single-registry lookups.

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