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

readOnlyHint=true already signals a safe read, and the description adds no behavioral detail such as return shape, error behavior, or whether this is a lightweight summary. It does not contradict 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 very short, but 'Prefer status' is cryptic and does not earn its place. The two fragments leave key information implied rather than stated.

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 single-parameter lookup with no output schema, the description should at least state what the returned chain data is and clarify the status preference. It does neither, so an agent would likely need to probe the tool or guess.

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% and id is described as 'chain slug', so the description's 'by slug' is redundant. No additional meaning or format detail is provided beyond the schema.

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 phrase 'One product by slug' conveys that the tool fetches a single item by its slug, but the resource is inconsistently called 'product' while the tool/title say 'chain', and no explicit verb appears. 'Prefer status' adds ambiguity rather than clarifying what this tool returns.

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?

'Prefer status' hints that the status sibling may be preferred, but it gives no condition, context, or exclusion for when to call get_chain instead. No other alternatives or prerequisites are mentioned.

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