Set an app cost model

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

Annotations already declare a non-read-only, non-idempotent, non-destructive mutation, so the safety profile is covered. The description adds only the faint hint that cost inputs are 'versioned' (implying prior versions are retained), but does not state whether history is preserved, that effective_at controls when the new version takes effect, or that repeated calls create additional versions rather than overwriting.

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?

It is a single front-loaded sentence with no filler, so nothing is bloated. However, for an 8-parameter mutation with a nested object, this degree of terseness is under-specification rather than efficient concision.

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?

No output schema exists and annotations do not cover versioning semantics, so the description carries the full burden for a complex mutation. It omits effective-dating behavior, unit conventions, retention of prior versions, and what assumptions is for — substantial gaps an agent needs before calling correctly.

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 description coverage is only 25% (just app_id and idempotency_key are documented), so the description must compensate. It names the three cost concepts but never explains that commissions and fees are basis points (0-10000), what variable_cogs_kind's bps vs per_unit_minor mean, or what effective_at and assumptions do — leaving several required parameters unexplained in either place.

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 phrase 'Version commission, payment fees and variable COGS used in profit decisions' identifies the resources being versioned, but 'Version' as a verb is oblique and the fragment never says plainly that it creates a new cost model version for a specific app. Combined with the name and title an agent can infer the purpose, but the description alone is vague on the 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?

There is no when-to-use guidance, no timing relative to profit-reporting workflows, and no mention of alternatives or prerequisites. The only clue to context is the trailing 'used in profit decisions', which does not tell an agent when to call this versus other configuration tools.

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