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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the 'Read only' line is largely redundant. However, the description adds genuinely useful behavioral context beyond the annotations: the data is a snapshot 'as Runsheet last recorded it' with a 'when it was last synced' field, telling the agent results may be stale rather than live.

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 short sentences that are front-loaded with the core purpose and the returned fields. The trailing 'Read only' is a minor redundancy against the readOnlyHint annotation, but nothing is wasted overall.

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 usefully enumerates the returned fields and flags the cached nature of the data, which is what an agent needs for a zero-parameter read. The only gap is the lack of routing guidance relative to sibling getters, which is minor for such a simple tool.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline is 4. No parameter meaning is needed or missing.

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 names a specific resource (the connected YouTube channel) and enumerates the exact fields returned (title, handle, subscriber count, total views, video count, last sync), so the purpose is unambiguous. It does not explicitly differentiate itself from siblings like runsheet_get_schedule or runsheet_get_library, but the 'channel' resource is distinct enough that an agent can separate it from the other getters.

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?

Usage is only implied: it's a read of the channel's recorded state, but there is no statement of when to call it versus the sibling getters or of any prerequisites. The phrase 'as Runsheet last recorded it' hints at cached/local data as opposed to a live API call, which is mildly useful, but no explicit when/when-not guidance is given.

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