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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing resolution semantics: the text is derived from the parent video_settings with per-platform overrides applied, which an agent could not infer from annotations or schema.

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?

Two sentences, front-loaded with the return payload and followed by the usage condition. No filler or redundant restatement of the title.

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?

There is no output schema, but the description compensates by enumerating what is returned, and the sole parameter is fully documented. The only gap is behavior on an invalid or deleted video_post_id (error vs. empty result), which is minor for a single-item read.

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?

With 100% schema description coverage, the single parameter is fully documented in the schema, including where to obtain the value (list_video_uploads, list_scheduled_posts, create_post_draft). The description adds no parameter-level meaning beyond that, so the baseline 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?

States a specific verb and resource ("Returns full detail on a single video post") and enumerates the returned fields — status, platform, timestamps, resolved caption/title/description. This clearly distinguishes it from sibling list tools like list_video_uploads and list_scheduled_posts.

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?

"Use before update_post when you need to know the current text" gives an explicit trigger and names a sibling tool as the downstream consumer. It does not cover when-not-to-use (e.g., batch scenarios where batch_update_posts or list tools suffice), but the routing guidance is clear.

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