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

Goes beyond the annotations by disclosing a concrete rate limit (120/min) and the exact return field set, plus the scope limit that it does not grade the site. The annotations already cover readOnly/idempotent/openWorld, so this is additive; it stops short of explaining what fields like 'outcome' vs 'status' vs 'reason' actually mean, which matters since there is no output schema.

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 compact sentences, front-loaded with the core action and constraint, then the return contract, then the routing guidance. Every sentence carries distinct information with no repetition of the title or schema.

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 2-parameter read-only check with full schema coverage and complete annotations, this covers nearly everything an agent needs, including the return shape that would otherwise be missing without an output schema. Minor gap: the returned fields are listed but not defined, and no guidance on error/not-found handling.

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 carry their own descriptions with examples (origin hostname, id such as ard/llms-txt/robots.txt). The description adds no parameter meaning beyond that, so the baseline 3 applies.

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 and scope: check ONE public origin over HTTPS for a SINGLE standard or manifest, explicitly 'without grading the full site.' This cleanly separates it from probe (all 37 paths) and validate_manifest (A+–F grading) named in the same breath.

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?

Explicit when-to-use plus two named alternatives with the condition that selects each: 'use has for a fast single-file check; use probe to scan all 37 paths at once, or validate_manifest for A+–F conformance grading.' Nothing is left to inference.

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