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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, but the description goes well beyond by detailing the matching algorithm (every term must match, punctuation ignored), the ranking order (exact ID/name, phrase, etc.), and deduplication behavior (each indicator ID appears once). This provides valuable behavioral context not available in annotations or 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?

The description is dense but well-organized: first sentence states purpose and return, second states the constraint, then matching behavior, then dedup, and finally references to companion tools. Every sentence contributes new information; there is no fluff or redundancy.

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 multiple filters and ranking logic, the description covers all necessary aspects: what it returns, how matching works, ranking, deduplication, the minimum filter requirement, and how to obtain valid filter values. Given an output schema exists for return format, the description is sufficiently complete for an agent to call it correctly.

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% with parameter descriptions, but the tool description adds significant meaning by explaining how the query parameter matches terms across ID, name, and description, and how topic_id/source_id act as filters with references to list tools. It also clarifies the 'at least one' constraint, which the schema doesn't enforce as required fields.

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 ('Searches') and resource ('the 29,500+ World Bank indicator catalog'), and immediately differentiates from siblings like worldbank_search_projects by specifying keyword, topic, or source filters. It also states the return value and its downstream use ('chaining into worldbank_get_data'), making the tool's purpose unambiguous.

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?

It explicitly states the precondition 'At least one of query, topic_id, or source_id must be provided' and directs users to worldbank_list_topics and worldbank_list_sources for valid IDs. The mention of chaining into worldbank_get_data clearly implies this is the search step before data retrieval, and the distinction from other search tools is clear from context.

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