Pay: subscriptions resync

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

Annotations already declare destructiveHint=true and openWorldHint=false, so the safety profile is partly covered. The description adds genuinely new context: it overwrites the stored record, requires project-admin rights, errors on Apple subscriptions, and advises confirming with the user first. It stops short of detailing irreversibility or the returned payload shape.

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 tight sentences, front-loaded with the action and its mechanism, then the usage trigger, the Apple limitation, and the destructive warning. No filler, though the 'project admin' note is repeated in the first two sentences.

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 mutation with no output schema, the description covers purpose, prerequisites (project admin), usage trigger, unsupported provider, and a confirmation warning. The only real gap is that it does not describe the shape of the returned result beyond 'returning the result'.

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?

Only one parameter and schema description coverage is 100% — the schema already documents 'id' and even points to pay_subscriptions_list for discovery. The description adds no further semantics about the id format or lookup, so the baseline of 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?

States a specific verb and resource (re-sync a subscription) and explains the mechanism precisely: fetch the live Stripe state and overwrite the stored record. The 'project admin' qualifier and the Stripe-vs-Apple distinction clearly separate it from siblings like pay_subscriptions_relink or pay_subscriptions_get.

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 trigger condition ('use it when the status shown disagrees with Stripe') and a when-not ('Apple subscriptions aren't supported yet and return an error'). It does not name a sibling alternative for read-only inspection (e.g. pay_subscriptions_get), so it falls just short of the full when/when-not/alternatives bar.

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