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

The annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint false. The description's read-only and 'never posts or fulfills orders' largely restate those annotations rather than adding new behavioral details like pagination, auth, or rate limits. This is acceptable given the annotations, but the description adds only minor extra context.

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?

Two succinct, front-loaded sentences with no filler: the first names the data categories, the second reinforces the read-only boundary. Every word contributes to selecting or using the tool correctly.

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 zero-parameter, read-only tool with an output schema, the description provides enough information about the tool's domain and contents. It could be stronger by explicitly naming siblings like get_market_status or the prepare_* tools, but nothing essential is missing for calling this tool 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?

The tool has zero parameters, so there is no parameter documentation burden. The schema coverage is 100%, and the baseline for a zero-parameter tool is 4. The description does not need to clarify any parameters.

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 states a specific verb ('Read') on a specific resource ('aggregate listings, bids, one-hour claims, and 24-hour transfers'). It also distinguishes itself from the many prepare_* transactional siblings by explicitly saying 'never posts or fulfills orders', so an agent can differentiate this read tool from the write/transaction tools.

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 clearly says what this tool is for: reading the aggregate market feed components. The line 'Read-only; never posts or fulfills orders' gives an explicit exclusion for transactional operations, though it does not name a specific alternative tool to use in those cases.

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