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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds operational behavior: it is a polling/retry tool, requires sessionId under certain auth conditions, and should not trigger new agent-link setup. This adds useful context beyond the annotations, though it does not go into error or timeout behavior.

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 description is front-loaded with purpose and return values, then gives sequencing, auth handling, and guardrails. The 'Never web-search' directive is a bit abrupt, and the conditional sessionId sentence is dense, but overall each sentence contributes necessary guidance.

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 names the return fields ('status draft|chosen and chosenOptionId'), which is sufficient for a simple read-only poll. It also covers the key sequencing and auth conditions. It does not describe exact error responses or JSON shape, but those are not essential given the tool's simplicity.

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 only 50% because choice_set_id has no schema description. The description compensates by explaining the choice set originates from present_choices and that its identifier is used as choiceSetId before create_purchase. The sessionId parameter is already richly described in the schema, and the description reinforces the retry behavior. This is meaningful added semantics, though it could be more explicit about how choice_set_id is obtained.

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 says exactly what the tool does: 'Poll a choice set from present_choices' and states the meaningful return values, 'status draft|chosen and chosenOptionId.' This clearly distinguishes it from the many other get_* siblings by tying it to present_choices and the post-choice status.

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 explicit timing: 'Call after present_choices when waiting for the owner, or before create_purchase to attach choiceSetId.' It also tells the agent what not to do in the auth-failure case: 'Never begin_agent_link again' and 'Never ask the owner to edit connector settings or reconnect.' This is actionable and specific.

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