list_recordings

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false. The description adds meaningful behavior beyond these: it does not fetch provider pages, media bytes, or transcripts, and it defines how pagination and merging should work. This gives the agent a precise mental model with no contradiction.

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 compact and front-loaded with the core purpose, followed by return contents, pagination, and negative scope. Every sentence adds useful information, though the 'nextStartAt' vs 'startAt' phrasing could be tightened.

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 responsibly enumerates the return contents and behavioral boundaries. It covers pagination and non-fetching behavior adequately for a read-only listing tool. The main gap is the unclear mapping between the pagination token and the startAt parameter, plus the lack of any mention of maxDetails.

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 description coverage is only 33%, so the description must compensate for undefined parameters like startAt and maxDetails. It mentions 'Resume with nextStartAt' but never explains that the input parameter is startAt, nor what maxDetails controls. The description adds no direct semantic value for two of the three parameters.

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 states a specific verb ('Discover') and resource ('recording and published caption links'), and scopes it to the visible course outline and bounded module/topic metadata. It also differentiates the tool from nearby siblings by specifying what it returns (provider labels, exact sources, native read_material targets) and what it does not fetch.

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 gives clear usage context: it is for discovering links without fetching media, and it explains pagination behavior ('Resume with nextStartAt and merge by URL; coverage applies to the current call'). It does not explicitly name as alternatives read_recording or read_material, but the boundary it draws is sufficient for most selection decisions.

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