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

With no annotations, the description carries the behavioral burden and does it well: it discloses the one-charge batching, the independent reporting of sub-checks, and that a failure in one area does not invalidate the others. It does not cover output shape or potential rate/quota side effects, but the disclosed traits are material.

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, each earn their place: bundle composition, cost/usage advantage, and failure isolation. The word 'Bundle' is front-loaded and prevents mistaking it for a standalone check.

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 one-parameter composite tool, the description covers what is bundled, why to use it, and how sub-results behave. It lacks an explicit note on the returned report structure, which would fully compensate for the absent output schema, but this is a minor 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?

Schema coverage is 100%, with the schema already specifying a bare domain without scheme/path. The description only says 'against a domain,' adding no meaning 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?

Description names the exact verb/function — a bundle running seo_audit, domain_health_check, and email_deliverability_check against a domain — and thereby distinguishes itself from those standalone siblings. It also clarifies it is a composite call rather than a new check.

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?

States a concrete reason to choose the bundle over the alternatives: one call/one charge and cheaper than running the three tools separately. It does not explicitly state when to avoid the bundle and use a single tool instead, so it stops short of full when/when-not guidance.

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