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

With no annotations, the description carries the full burden and does real work: it discloses that reads happen live against the domain, that no discovered data is persisted, that no ownership or safety claim is made, and that every resource carries a sourceUrl for verification. It omits failure modes (domains with no discovery files), timeouts, and rate-limit behavior, keeping it short of a 5.

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 sentences that are front-loaded with the action, then the mechanism (named discovery locations), then the trust/provenance caveats. The path list is dense but earns its place by telling the agent what sources are actually consulted; there is no 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?

For a single-parameter tool with no output schema, the description adequately conveys that a single normalized answer is returned and that per-resource sourceUrl provenance exists. It stops short of describing the shape of the normalized resources or behavior on domains with nothing published, which is the main remaining gap.

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?

Only one parameter exists and the schema already documents it at 100% coverage ('Registrable domain, e.g. example.com'). The description's 'Given a domain' adds no format, normalization, or validation detail beyond the schema, 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 precise verb (read/discover) and resource (a domain's machine-readable resources at standard discovery paths) and describes the return ('one normalized answer'). The operation is unmistakably distinct from check_readiness and connect_domain, which imply testing and linking rather than live discovery.

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 frames the input ('Given a domain...') so the use case is implied, but it never states when to prefer this over check_readiness or connect_domain, nor any prerequisites or exclusions. A reader must infer that this is the lookup step of a discovery-then-connect flow.

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