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

With no annotations, the description carries the full burden and does well: it discloses the two-upstream-request behavior, that the return is ordinary video-search results rather than CSI-related or seed-similar videos, and that it cannot pass search_id. It omits auth/rate-limit/error context, but the load-bearing behavioral traits are covered.

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?

Three sentences, front-loaded with what the tool is, then routing guidance. Every sentence serves a purpose (definition, return clarification, alternative routing), though it is fairly dense and slightly repetitive about search_videos.

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?

No output schema exists, and the description compensates by stating the return is ordinary video search results. It covers the mechanism, routing, and continuation limitation; only minor gaps remain (no explicit return shape or permission notes) for a simple read-only helper.

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 baseline is 3, but the description adds rationale the schema lacks — it explains why offset/continuation is unsupported (no search_id plumbing) and reinforces that query_id is a topic queryId, not a video ID or keyword. This gives genuine added meaning beyond the field descriptions.

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 gives a specific verb+resource (CSI topic-to-video search helper), explains the two-request mechanism precisely, and explicitly distinguishes itself from search_videos, similar_videos, and a dedicated CSI related-video response. An agent can select it correctly 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?

It states when to use it (queryId known, queryText not), when to skip it (queryText already known, use search_videos directly), and when to use the alternative for pagination/filtering. Exclusions are explicit, including the missing search_id continuation case.

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