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

Annotations only declare write-ish, non-destructive, non-open-world, which is thin. The description adds substantial context beyond them: the file is copied into Slice, transcribed and searched with no further steps; the no-file path returns an upload_url; and it states hard limits (three hours, 4.5GB) plus the audio-only template behavior. This is exactly the extra behavioral detail annotations cannot carry.

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 trigger condition, then the two execution modes, then the follow-up and exclusions. Five sentences, each carrying distinct routing or behavioral information; nothing is redundant with the schema or annotations.

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 4-param tool with nested file object, enum, and an output schema, the description covers the trigger, both invocation paths, size/duration limits, and next-step routing. Since an output schema exists, return-value detail is correctly omitted apart from the one return value (upload_url) the agent must act on.

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 baseline is 3. The description goes further by explaining the conditional semantics of the optional `file` parameter (attached → passed directly; absent → upload_url flow) and what happens to the uploaded media, which is meaning the schema does not convey. It adds little about `target_seconds` or `content_type` beyond the already-detailed schema text, keeping it short of a 5.

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 first sentence states a specific verb+resource+outcome ('turn a podcast, interview, stream or other video into short clips'), and the rest of the description names the sibling alternatives it is not (transcribe_audio) and the follow-up tool (get_episode). An agent can separate this from every sibling without opening a 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?

Explicit when-to-use ('user wants ... turned into short clips'), explicit when-not ('only wants the words as text → transcribe_audio'; 'YouTube or other web links ... not supported'), plus the sequencing instruction 'Follow with get_episode'. All three routing decisions are handed to the agent directly.

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