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

Annotations indicate readOnlyHint=false and destructiveHint=false, meaning it's a non-read-only mutation. The description adds valuable context beyond annotations by disclosing the credit cost and stating that the building and camera angle remain unchanged, which helps set expectations.

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 description is two sentences long, front-loaded with the main action, and contains no redundant or filler wording. Every detail (visual transformation, invariants, credit cost) earns its place.

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?

The description covers the tool's purpose and cost, and the schema fully documents the parameters. However, it omits mention of the return value or whether the operation is asynchronous (likely via a job, given sibling get_job). Since there is no output schema, describing the result format would improve completeness.

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?

The input schema provides 100% coverage of both parameters (r2Path and imageUrl) with detailed descriptions, including the constraint that either one is required. The description does not add additional parameter-level meaning, so the baseline score of 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?

The description clearly states the action — 'turn a daytime listing photo into a magazine-style night scene' — with specific visual details (lights on, warm glow, dusk sky) and invariants (building/camera unchanged). This differentiates it from sibling tools like enhance_photo or virtual_staging.

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 description implies when to use this tool (when you have a daytime listing photo and want a night scene) and explicitly mentions a practical consideration (credit cost). It does not name alternatives or exclusions, but the context is clear enough for an agent to decide.

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