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

Annotations already cover the safety profile (readOnly, non-destructive, openWorld), so the description's job is to add context — and it does: it discloses the full status vocabulary including the non-obvious 'under_review' and 'failed' states, defines 'billable' as credits consumed, and names the underlying endpoint (POST /jobs/status). It omits rate limits or polling cadence, which keeps it from 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?

The key actions — what is returned and to poll until complete — are front-loaded in a compact two-sentence block. The long parenthetical list of status values and counters is dense but each item is genuinely informative, so little is wasted.

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?

With no output schema, the description carries the burden of describing return values and does so thoroughly enough for an agent to interpret a response. Nothing critical is missing for a single-parameter read, though guidance on what to do after 'complete' (e.g. fetching results) is absent.

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% and the schema itself explains that job_id comes from neverbounce_list_jobs or neverbounce_create_job. The description adds no format, range, or sourcing detail 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?

The description states a specific resource (a single verification job) and enumerates exactly what is returned: status, failure reason, timestamps, totals, bounce estimate and percent complete. That implicitly separates it from neverbounce_get_job_results and neverbounce_download_job_results, though the siblings are never named, so an agent must infer the boundary itself.

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?

"Poll this until status is complete" gives an explicit operational instruction and the terminating condition, which is exactly the guidance an agent needs for a status endpoint. It does not state what to do before a job exists or when to prefer get_job_results instead, so no exclusions are offered.

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