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

Annotations already mark the tool as read-only, idempotent, and non-destructive; the description adds valuable behavioral context beyond that, including that it reads a self-hosted official snapshot, returns stable codes, includes pagination and snapshot provenance, and covers only aggregate US futures/options markets. No statement 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?

The description is three focused sentences: purpose, return contents, and usage guidance. It front-loads the most important information and every sentence earns its place without redundant 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?

Despite having no output schema, the description lists the key return fields (codes, names, labels, families, scopes, latest date, pagination, provenance) and provides enough context to call the tool correctly. It also ties the search to a downstream history call, covering the typical agent workflow.

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 every parameter has a meaningful description with defaults and enum values. The tool description reinforces the use case but does not add syntax-level meaning 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?

The description opens with a specific verb and resource ('Search contract markets in LiveDataLink's self-hosted official CFTC Commitments of Traders snapshot') and clearly enumerates what is returned (stable codes, names, commodity/exchange labels, report families, scopes, latest date, pagination, provenance). It differentiates itself by stating it is a lookup/search tool for identifiers and explicitly noting it is 'not quotes or prices.'

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 gives concrete example queries ('find the CFTC code for gold', 'which COT markets cover crude oil?') and states the workflow context: 'resolve an identifier before a history call.' It also sets boundaries with 'Aggregate US futures and options markets only; not quotes or prices,' so an agent knows when not to use it.

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