update_texttrackRename a Vimeo caption track, change its language, or set it as the active default track for a video.
Rename a caption track, change its language, or make it the active one.
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | ||
| active | No | Make this the default track. | |
| language | No | ||
| track_id | Yes | Track id, from list_texttracks. | |
| video_id | Yes | Video id. |
Changes observed during successful MCP inspections.
v2.0.0Input schema / $schemaRemoved value: -"http://json-schema.org/draft-07/schema#"Input schema / additionalPropertiesRemoved value: -falsev1.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is largely covered. The description adds the notable behavior that the tool can flip the default/active track, but says nothing about permissions, partial-update semantics, or whether omitted fields are left untouched.
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?
A single front-loaded sentence listing the three mutations with zero filler. Appropriate size for a simple update tool.
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?
Covers all three mutable semantic fields, but omits that video_id and track_id are both required to address the track and says nothing about the effect on other tracks when active is set. With annotations covering safety/idempotency and the schema covering identifiers, it is serviceable but not complete.
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 60% and covers track_id, video_id, and active; the description supplies meaning for the two undocumented fields by mapping 'rename' to name and 'change its language' to language. That is roughly baseline value over a schema that already carries the identifiers.
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 specific verbs (rename, change language, activate) against a specific resource (caption track / texttrack). An agent can distinguish this from delete_texttrack, upload_texttrack, and list_texttracks by the mutation described, though the siblings are not named explicitly.
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?
No guidance on when to use this versus alternatives such as delete_texttrack or upload_texttrack, no prerequisites, and no mention that a track must already exist. The enumeration of editable fields implies the use case but nothing is stated about alternatives or exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.