AI Price

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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds a meaningful behavioral fact those annotations cannot express: no credits are consumed, i.e. this is a free evaluation path. It does not describe the returned price shape, but that is a minor gap given the read-only annotations.

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?

Two short sentences, zero filler, with the credit-free guarantee front-loaded before the input contract. Every clause carries 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?

No output schema exists, and the description does not explicitly say what is returned (a credit cost), though 'price ... in credits' strongly implies it. With 10 nested parameters and 0 required fields, the 'same as ai_generate' pointer is the key completeness aid and is present, so the definition is sufficient without exhaustively enumerating inputs.

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 90%, so the schema already documents nearly all 10 parameters. The description adds a genuinely useful cross-reference ('same inputs as ai_generate'), telling the agent the parameter contract mirrors that sibling tool rather than being a reduced set. It adds no per-parameter detail beyond this, which is acceptable at this coverage level.

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) and resource (an AI generation) with an explicit scope qualifier: 'without spending anything'. It also directly relates itself to the sibling ai_generate ('Same inputs as ai_generate'), so an agent can tell these two apart without opening either 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?

The dry-run framing ('without spending anything') clearly implies when to use this instead of ai_generate: check cost before committing credits. However, there is no explicit when-not or named alternative, so the routing is inferred rather than stated.

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