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

Goes well beyond the annotations by disclosing the actual sink chain: POST JSON to LEAD_WEBHOOK_URL, fall back to emailing only the KOB inbox via Resend, and fall back again to server-side logging with the lead still returned. It also rules out side effects (no restaurant email, no Google mutation), which the openWorldHint=true annotation cannot express on its own.

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?

Front-loads the action and its precondition, then packs the sink/fallback behavior into tight conditional clauses. Dense but every sentence carries load; only the back-half fallback detail could arguably be trimmed.

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 9-parameter, non-idempotent, open-world write with no output schema, the description covers the important unknowns: what is transmitted, where it goes, what happens on each configuration fallback, and what is never done. It leaves return-value shape slightly vague ('the result still contains the lead') but that 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 description coverage is only 33% across 9 params, so the description must compensate and it only partly does: it explains that consent must be true and that auditSummary is a short, verified-findings-only summary. Fields like town, email, notes, placeId, website and restaurantName get no elaboration here, though the self-explanatory names carry most of the load.

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+resource ('Record a trial lead') plus the trigger condition, which is enough to distinguish it from every sibling (none of which touch leads). An agent can tell immediately this is the outbound lead-capture sink, not an audit or lookup tool.

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?

Gives an explicit precondition ('after the user typed their details and asked to be contacted') and two exclusions ('Never email the restaurant. Does not change Google.'). It stops short of naming an alternative sibling to use instead, but for a terminal capture action there is no competing tool to route to.

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