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

Annotations already declare the tool read-only, idempotent, and non-destructive. The description adds useful context beyond that by noting that no API key is required and by describing the response shape: grouped by category with endpoint count, credit range, and available data. This goes beyond what the annotations alone reveal.

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 core purpose is front-loaded effectively, but the description becomes one very long parenthetical enumeration of categories and examples. While informative, this reduces scannability; the same information could be delivered more concisely as a short category list or shorter summary.

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 zero-parameter, read-only catalog listing tool with no output schema, the description is largely complete: it states the full scope, the output contents, the grouping scheme, and the lack of an API key requirement. It lacks explicit sibling-routing guidance, but that is not essential for understanding this particular tool.

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?

This tool has zero parameters and 100% schema coverage, so there is no parameter documentation burden. The description appropriately adds no invented parameter details and instead communicates access context and result contents.

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 opens with a specific verb and resource: 'List all 65 platforms available through SocialCrawl.' It then clarifies the scope by enumerating covered categories and stating the returned fields, making it clearly distinguishable from a sibling like socialcrawl_list_endpoints.

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 implies the tool is useful for browsing the platform catalog and selecting platforms by category, credit range, or available data. However, it never explicitly explains when to choose this over related tools such as socialcrawl_list_endpoints or socialcrawl_discover, and it provides no exclusions or alternative routing guidance.

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