estimate_video_cost

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

Annotations declare readOnlyHint=false and destructiveHint=false, and the description adds real context beyond them: the call persists a quote ("Save"), returns alternative entitlement costs, and dictates display filtering. It does not contradict the annotations, though it never states persistence duration or whether saved quotes can be reused.

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 purpose is front-loaded and the text is short, but the second half is dense agent-facing display policy ("show only universal credits...") that reads as an output-formatting instruction rather than tool selection guidance. "10-minute" is an unexplained qualifier that adds noise.

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 13-parameter, 62%-coverage tool with no output schema, the description leaves many parameters and the returned cost structure only loosely described (a single reference to display.estimated_costs). It is adequate but does not fully close the gaps left by the missing output schema and partial parameter docs.

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 62%, so some parameters (notably the bare model_type) are undocumented in the schema. The description compensates only partially by naming default_model_type as the source, and leaves content/duration/mode semantics to the schema. Marginal value over the structured fields.

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 names a specific action (Save a video quote) and explicitly rules out generation ("Does not generate"), which separates it from siblings like generate_video. The odd "10-minute" qualifier and the term "quote" versus the tool name "estimate_video_cost" leave slight ambiguity about what exactly is being saved, but the core purpose is discernible.

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?

It gives one concrete prerequisite ("Unless the user specified a model, pass default_model_type from list_video_models") and a negative boundary (does not generate). However, it never says when to prefer this over estimate_image_cost / estimate_music_cost, nor does it state when an estimate is required before generate_video, leaving usage largely implied.

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