Estimate monthly token cost

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

Annotations already declare a safe, idempotent, read-only, closed-world computation, so the safety bar is met. The description adds real context beyond that: the pass-rate model ('cost per accepted result, counting retries') and the sourcing requirement for prices. It doesn't discuss rounding, currency, or accuracy caveats, which keeps it short of a 5.

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?

Effectively one sentence, front-loaded with the core purpose. It is dense with parentheticals but every clause carries information; there is no filler. Not perfectly scannable, so short of a 5.

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?

An output schema exists, so return-format explanation is unnecessary, and annotations cover the safety profile. Parameters are fully documented in the schema. The remaining gap is the retry/pass-rate computation mechanics, which are gestured at but not fully specified.

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 100%, so every parameter is already documented, establishing a baseline of 3. The description restates the cached-input share and pass-rate parameters and clarifies that retries count toward cost, which adds marginal meaning but largely duplicates the schema.

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 states a specific verb (estimate) and resource (monthly token cost) and enumerates the driving inputs. It is clearly distinguishable from the sibling modelfinder_estimate_memory by resource (cost vs. memory). An agent knows exactly what this computes.

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 phrase 'Planning estimate' signals it is for pre-hoc budgeting rather than measured spend, and it states that prices must come from the provider's official pricing page. However, it never names an alternative tool or an explicit when-not condition. Usage is only implied.

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