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

Annotations only cover the safety profile (readOnlyHint=false, idempotentHint=true, destructiveHint=false, openWorldHint=true). The description adds behavior the annotations cannot convey: the URL is stable while the checkout stays open, the tool refuses when the charge is not due or online payment is disabled, no tool accepts card details, and auth is required.

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?

Front-loaded with the trigger condition, then inputs, then return behavior, then failure modes and auth. Six short sentences, each carrying a distinct operational fact with no padding.

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?

A mutation/action tool with no output schema, yet the description still tells the agent what comes back (a URL), what to do with it (hand it to the person), idempotency behavior, refusal conditions, and auth requirements. Nothing needed to call it correctly is missing.

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% and both properties already document their format and source tools, so the schema does the heavy lifting. The description's 'one due charge' restates the schema's 'id of a due charge on that case' rather than adding new syntax or constraint detail; baseline 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: 'Opens a hosted checkout for one due charge and returns its URL.' It also names the sibling it is not (evictions_list_case_charges for paid-status checks), so an agent can distinguish it from the other 17 tools without opening a schema.

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?

Explicit trigger ('when the person wants to pay a due charge'), explicit exclusion ('Do not use this to see whether a charge is paid'), the named alternative, the required inputs, and the precondition (account via sign-in or API key). Nothing is left to inference.

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