update-video

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

With no annotations provided, the description carries the full responsibility for disclosure. It states the full-replace semantics on snippet/status parts, the read-before-write behavior to preserve omitted fields, and the 50 quota unit cost. This adds meaningful behavioral context beyond the schema, though it doesn't mention auth prerequisites or error handling.

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: the first states the action and affected fields, the second explains the replace semantics and quota cost. Every sentence is informative and there is no redundant or filler text. It is front-loaded with the core purpose and concisely structures additional context.

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?

Given the complexity (10 parameters, no output schema, no annotations), the description covers the key behavioral aspects (read-modify-write, full-replace, quota cost) and clarifies that omitted fields retain their current values. It doesn't describe return values, but for a mutation tool this is less critical. Overall it is sufficiently complete for an agent to invoke correctly, though it could specify what the response contains.

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 has 100% coverage with descriptions for every parameter (e.g., 'New title (unchanged if omitted)'). The description partially overlaps by listing fields and adds the key behavioral note about full-replace, but it does not add per-parameter semantics beyond what the schema already conveys. Per the baseline rule, this warrants a 3.

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 verb ('Update') and resource ('a video') and enumerates the specific fields (title, description, category, tags, privacy, status flags). This distinguishes it from sibling tools like upload-video or update-playlist, making the tool's primary purpose unambiguous.

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 the tool is for updating video metadata and notes the full-replace/read-first behavior, which hints at when to use it (when you need to change fields without overwriting omitted ones). However, it does not explicitly state alternatives or exclusions (e.g., 'use set-thumbnail for thumbnails'), so the guidance is implied rather than explicit.

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