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

Even with annotations already declaring readOnlyHint/openWorldHint/idempotentHint, the description adds substantial behavioral detail: account/paywall requirements, parallel facet decomposition, the exact findings packet composition (verbatim evidence + confidence + source + fetched_at + citation), explicit gaps[] semantics with a 'never invented' guarantee, contradictions[] for standard/thorough, a `hop` field, citation_uri always fetchability, semantic excerpting rather than head-truncation, and latency expectations. This far exceeds what annotations convey.

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 and front-loaded with the most critical routing signal ('ACCOUNT REQUIRED' and 'use ask_pipeworx instead'), and every major behavioral point is present. However, some redundancy exists: the depth-level explanation in the description partially repeats the input-schema depth description, and the latency sentence could be tightened. Still, no sentence is filler.

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 complex tool with no output schema, the description fully compensates by specifying the return packet contents, the gaps[]/contradictions[] fields, the citation_uri guarantee, and performance expectations. It also covers auth prerequisites, alternative tool routing, and nuanced depth behavior. An agent has everything it needs to select and invoke this tool correctly without inspecting schema further.

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%, so the baseline is 3. The description adds meaningful color beyond the schema: it ties depth tiers to cost ('thorough needs a paid plan'), explains behavior per depth level ('re-angles unanswered gaps', 'chases the best leads'), and clarifies that 'broad/multi-part is fine — decomposition is the point' for the question parameter. This enrichment justifies a 4.

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+resource pair: 'Grounded multi-source research across Pipeworx's 1500 STRUCTURED data sources' and clearly states it decomposes questions into facets routed 'IN PARALLEL' to 5,743 tools. It distinguishes itself from siblings by explicitly saying 'this is NOT open-web search' and by directing single lookups to ask_pipeworx. This is a precise, non-tautological statement of purpose.

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 provides explicit when-to-use and when-not-to-use guidance: 'If you are not signed in, use ask_pipeworx instead' and 'For a single lookup use ask_pipeworx.' It also scopes the ideal use case to 'broad/multi-part questions over structured data' and names alternatives like ask_pipeworx and open-web search. No ambiguity remains about routing.

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