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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds real behavioral value beyond that: it discloses that all hosted views are aggregated together, that incompatible family classifications are explicitly preserved, that output is provenance-backed, and that the data is not real-time. No misleading claims.

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?

Three sentences, front-loaded with the core operation and followed by output contents, usage examples, and caveats. Every sentence carries information, though the middle sentence about preservation of family classifications is dense and could be tightened.

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, the description does the work of describing the pack's contents and its provenance framing, plus a clear data-freshness caveat. It is nearly complete for a two-parameter read-only aggregation tool; only explicit routing versus sibling COT tools 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 description coverage is 100% and both parameters (market, response_format) are fully documented with constraints and enum values. The description only implies the single-market scope but adds no syntax or format guidance beyond the schema, so the baseline of 3 is appropriate.

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 (combine) and resource (all hosted official CFTC COT report-family and scope views) scoped to one contract market, and describes the output contents (open interest, largest absolute category net, preserved family classifications). It distinguishes itself from single-view siblings by emphasizing aggregation of 'all ... views,' but never names the concrete alternatives (cftc_cot_latest, cftc_cot_history, cftc_cot_compare), so differentiation is inferred rather than explicit.

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?

Provides concrete invocation examples ('build a COT evidence pack for gold', 'show every CFTC positioning lens for crude oil') and states the framing ('designed for research synthesis') plus exclusions ('not real-time data, a forecast, or trading advice'). It gives clear context for use but does not explicitly say when to prefer this over the sibling single-view tools.

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