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

Beyond the annotations it discloses the consequences that matter: the courtesy is permanently consumed and does not return, the next project is not a courtesy, work already produced during the courtesy stays free, and all subsequent corrections/renders bill the wallet. It also states the `write` permission requirement, the $0 cost, and the returned fields (`leftCourtesy`, new `courtesy` verdict, `quote` with wallet balance) — a genuinely rich behavioral profile for a destructive mutation.

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 action and target are front-loaded in the opening clause, and the trailing fragments ('Requires `write`. $0.') are efficient. However, the body is one long run-on sentence with stacked parentheticals that makes it slower to read than necessary; splitting the trigger, the effect, and the return values into separate sentences would cost no 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?

With no output schema, the description usefully enumerates the return values (`leftCourtesy`, `courtesy` verdict, `quote`), and it covers permissions, cost, irreversibility, and the trigger condition. The remaining gap is edge-case behavior — what an invalid or non-courtesy project_id yields, and whether repeat calls are no-ops given `idempotentHint: true`.

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 50%: `reason` is documented in the schema but `project_id` is bare. The description partially compensates by pinning the target as 'the account's first project (the one-minute piece the house produces)', which tells the agent which project_id is expected, but it never says what happens if a different project_id is supplied.

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 names a specific verb and resource (leaving the house's courtesy on the account's first project) and identifies the exact piece involved — the one-minute capped-corrections/renders project. It is distinguishable from siblings like `produce` or `list_projects` because it explicitly frames itself as the alternative to opening a new project. It stops short of 5 because the domain term 'courtesy' is never defined plainly and the sentence must be parsed twice to extract the core action.

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 states a precise trigger — the `payment-required` cap (`tope_correcciones_alcanzado` / `tope_renders_alcanzado`) — and names the alternative behavior (open a new project instead). What is missing is any explicit when-not guidance, e.g. what to do if the author wants to stop entirely or if the wallet balance is insufficient.

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