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

Annotations cover the safety profile (readOnly, idempotent, closed-world), and the description adds real operational context beyond them: each call consumes one unit of a monthly quota, results are capped by max_results, verified records are surfaced before unverified ones, and preflight may legitimately return nothing. The quota disclosure in particular is information an agent cannot get from structured fields.

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?

Four dense sentences ordered purpose → when to use → what comes back/cost → exclusions. Nothing is padding and the most decision-relevant routing rule (preflight mode) is front-loaded.

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 an output schema present the description need not enumerate return fields, yet it still flags the verified/unverified ordering and the empty-result possibility. For a 9-parameter tool with nested args_shape, an agent has everything needed to invoke it correctly.

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%, so the baseline is 3, but the description adds functional meaning: it explains the lookup vs preflight split and that preflight requires args_shape, tying the parameters to a workflow rather than just restating types.

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 opens with a specific verb and resource — 'Check for known failures and workarounds' — and scopes it to third-party tool calls. It is unambiguous what the tool returns (workarounds, verified first), though it never explicitly contrasts itself with the kb_confirm/kb_dispute/kb_report siblings.

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?

It gives concrete triggers ('a tool call errored, returned an unexpected shape, or you are about to call a tool you have not used in this session'), tells the agent to switch mode to preflight in the second case, and states two explicit exclusions (non-tool-call questions, tools of this server).

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