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

With readOnlyHint true and destructiveHint false, the annotations already establish the safe-read profile; the description adds that events are append-only, scoped to the caller, and that debit reason digest_success follows a successful digest. It does not describe the response format or clarify the rss/atom/feed item aspect from the title.

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?

Two compact sentences deliver the core purpose and one important event-trigger fact without filler. The second sentence is dense and somewhat cryptic, but it earns its place by explaining when the digest_success debit event is created.

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 zero-parameter, read-only tool with annotations, the endpoint and event semantics provide a usable picture. However, there is no output schema and the title advertises rss/atom/feed items that the description never addresses, leaving the returned shape ambiguous.

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?

The tool has no parameters, and schema coverage is effectively 100% via an empty input schema, so there are no parameter semantics to document. The description's caller_id reference appears to be authentication context, not an input parameter, and no additional parameter guidance is needed.

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 identifies the resource (credit events for the caller_id) and the exact endpoint (GET /credits/events), so an agent can see this is a read-only ledger listing rather than a balance or purchase tool. It does not explicitly contrast itself with sibling tools like credit_balance or digest_feed, and the title's mention of rss/atom/feed items is not integrated.

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?

The description implies the tool is for viewing caller-scoped credit ledger events and adds a relevant event trigger (digest_success after a successful digest), but it never states when to prefer this tool over credit_balance or digest_feed. There are no explicit when-not-to-use or alternative routing instructions.

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