putCaptionTranslation

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

Annotations only give the generic write/non-destructive/local profile, and the description adds substantial behavior: merge semantics into an existing layer, first-call creation, atomic refusal of the whole call on unknown unit ids, and the guarantee that the transcript is never altered. This is far beyond what the annotations convey.

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?

It is dense but front-loaded with the core action and structured by parameter, with every sentence contributing a non-obvious constraint. It is slightly long, but no sentence is filler.

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 mutation tool with no output schema and low schema description coverage, the description covers behavior, merge/atomicity semantics, parameter meaning, and the relationship to the caption-switching sibling. Only assetId's precise semantics are left implicit.

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 only 20%, so the description carries most of the load: it explains the units array shape {id, text}, that the id comes from getCaptionTranslationUnits, what language means (layer code like fr or pt-BR), and that label defaults to the code. assetId remains implicit and projectId's meaning is only in the schema, so it falls just short of full compensation.

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 opens with a specific verb and resource: storing translation of caption units for one asset into a language layer. It also names the sibling that supplies input ids (getCaptionTranslationUnits) and the sibling that performs the adjacent action (setCaptionSettings), so an agent can place it precisely in the toolset.

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 states when to use this versus alternatives: use setCaptionSettings to actually switch captions to the layer, use getCaptionTranslationUnits to source unit ids. It also gives operational guidance (send long transcripts in batches since the first call creates the layer), which is exactly the routing an agent needs.

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