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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds value beyond them: free, no key needed, keyless-try behavior, that api_key is ignored when signed in, and that with a key the response also reports whether existing credits cover the job. It stops short of describing output shape, which the output schema covers.

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-loads the key fact ('Free, no key needed') and keeps to three purposeful sentences. The pricing-tier enumeration is dense but directly relevant to the quote the tool returns; nothing is wasted, though it borders on verbose.

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?

For a read-only pricing tool with a full output schema and 100% schema coverage, the description covers cost model, key handling and the recommended call timing. Little an agent needs in order to invoke 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%, so rows, api_key and questions_per_text are already documented in the schema (including the 'leave out' semantics). The description adds useful pricing-tier context but no new per-parameter syntax or format beyond what the schema carries, so 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 (price/quote) and resource (a job defined by texts and questions), and precisely says what comes back: credits needed and dollar cost. An agent can distinguish this from hunch_ask, hunch_multi and hunch_balance from the description alone.

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?

Gives an explicit usage directive: 'Call it before a large batch so you can tell the person the price first.' It also explains the keyed vs keyless case, but names no alternative sibling or when-not-to-use condition.

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