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

Annotations (readOnlyHint=true, openWorldHint=true, idempotentHint=true, destructiveHint=false) already establish a safe read-only profile, and the description adds rich behavior beyond them: honest gaps[] reporting ("never invented"), stable and fetchable pipeworx:// citation URIs, semantic excerpting of large records, latency expectations (15-60s, thorough up to ~90s), and a paid-plan gate for thorough depth. Nothing in the description contradicts the annotations.

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?

Every sentence carries valuable information, but the description is one dense wall of text with heavy parenthetical asides and em-dash digressions, making it harder to parse than it should be. Drafting artifacts such as the stray quote in depth:"thorough" and inconsistent sibling-name references (ask_pipeworx vs. close variants) slightly undermine clarity. The front-loading of account requirements and the core distinction from open-web search is good, but structure is not.

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?

With no output schema present, the description fully carries the return-value burden and delivers: findings packet contents (verbatim evidence + confidence + source + fetched_at + citation), gaps[] and contradictions[] semantics, hop field, citation resolvability guarantees, auth/eligibility constraints, and expected latency. For a complex tool with depth modes, parallel routing, and explicit honesty guarantees, nothing an agent needs to decide to invoke it is missing.

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 schema already documents question and depth well; the description adds meaning beyond it by explaining what each depth mode does operationally (single hop vs. gap-recovery hop vs. lead-chasing iteration, plus contradictions[]), the paid requirement for thorough, and latency implications. The natural-language question parameter needs no further explanation.

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+resource+scope: "Grounded multi-source research across Pipeworx's 1506 STRUCTURED data sources... in ONE call — this is NOT open-web search." It names the ideal use case ("Best for broad/multi-part questions over structured data") and explicitly differentiates itself from ask_pipeworx for single lookups. An agent can immediately tell what this tool is and what it is not.

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?

Gives explicit when-to-use and when-not-to-use guidance with named alternatives: "If you are not signed in, use ask_pipeworx instead," "For a single lookup use ask_pipeworx," and breaking/current-news topics should prefer the news-routing sibling. It also ties depth selection to behavior (gap recovery, contradictions scan, paid tier) so an agent knows which mode fits which need.

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