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

The annotations already mark this as read-only, and the description adds meaningful behavioral context beyond that: it operates in Stripe test mode, uses test cards only, and makes no real money moves. This is valuable safety-related disclosure not present in the annotations.

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 short and front-loads the core purpose in the first sentence. The Stripe test-mode notice is slightly redundant ('test mode', 'test cards only', 'no real money moves'), but overall every clause contributes useful information.

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?

Even without an output schema, the description states the main returned information (fill count and state) and the optional email behavior, and the schema covers parameters. It does not enumerate possible state values, but that is not necessary for correct invocation.

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 schema already describes both parameters at 100% coverage, so the description does not need to carry the parameter-documentation burden. It lightly reinforces the email parameter ('also see that person's commitment') but adds little beyond the schema's own wording.

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 (one chain) and the data it reports (fill count, state, and optionally a person's commitment). It is terse and uses a noun phrase rather than an explicit verb like 'returns', but it is specific enough to distinguish from siblings like list_chains and book_stats.

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?

There is no explicit guidance on when to use this tool versus alternatives such as get_chain or book_stats. The only usage-related signal is the Stripe test-mode warning, which is about safety rather than tool selection.

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