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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new behavioral context: that the underlying robots.txt data is advisory rather than proof of blocking, and that attribution to the blocklist page is required when using the result. These are interpretation and usage constraints an agent could not get from 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?

Three short sentences, front-loaded with what the tool returns before the interpretive caveat and the attribution requirement. No filler, though 'Credit the blocklist page' is terse enough to be slightly ambiguous without surrounding context.

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 summary tool with no output schema, the description covers the substance of the result (which retailers name AI agents), where the fuller data lives, and the key interpretive limit. It omits freshness or caching behavior and does not clarify how the summary is scoped, but nothing essential to calling 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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. The description correctly spends no words on parameter 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?

The description gives a concrete verb and resource: summarizing which retailers' public robots.txt files name AI agents, plus a pointer to the full check. It does not reference the very similar sibling which_retailers_block_agents, so the agent must infer the distinction from the caveat that robots.txt is 'a request, not proof of a block' rather than from an explicit differentiation.

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?

There is no explicit statement of when to use this tool versus the near-duplicate which_retailers_block_agents, nor any prerequisites or exclusions. The phrase 'where to read the full check' implies this is a summary layer over a more complete source, but that implication is never tied to a named alternative.

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