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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real behavior beyond them — transcripts are suppressed by default to avoid large payloads, only has_transcript + transcript_length are shown, and an unknown id yields { error }. Not fully rich (no pagination limits discussion beyond transcript_max_chars, no rate/auth notes).

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?

Front-loaded with the resource and its returned fields, then the transcript caveat, then the error case. Dense but every clause earns its place; no 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?

With no output schema, the description carries the return-shape burden and does so: it names the fields returned, explains the transcript omission and its workaround, and documents the error response. Nothing essential for a correct call is missing.

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 100%, so the schema already documents the four parameters. The description adds nuance the schema lacks: the default-off rationale, the coupling of include_transcript with transcript_offset for paging, and the error return for an unknown id.

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 (get) plus resource (one YouTube video) and enumerates the returned fields (upload date, abstract, playlists, speakers, languages, watch URL, citable amira_url). An agent can distinguish this from siblings like get_research_item or search_videos without opening the schema.

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?

Gives clear operational context: transcript is omitted by default and the caller should pass include_transcript=true and page long transcripts. It does not, however, name an alternative tool or say when not to use it (e.g. when search_videos suffices), so it stops short of explicit when/when-not routing.

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