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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so "No write. Idempotent." largely repeats structured data rather than adding new information. The one genuinely useful behavioral detail is that an omitted campaign_id silently falls back to the default Campaign deck, though that too is duplicated in the schema.

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 short sentences with the resource and scope front-loaded, and no filler. The trailing "No write. Idempotent." is slightly wasted given the annotations, but overall it is tight.

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 read-only list tool with full schema coverage, the definition covers selection but says nothing about what a summary contains, ordering, or whether results are bounded — and with no output schema, the description is the only place that could convey this. Adequate but with a clear return-value gap.

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 100%, so both parameters are already fully documented, and the description only restates campaign filtering and sequence-based filtering. No extra syntax or format detail is added beyond what the schema provides, so the baseline of 3 applies.

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 and resource ("List participant watch summaries in this Space") plus the two filtering dimensions, which is more than a restatement of the name. It does not name the write counterpart (write_watch_summary) or other read siblings as alternatives, but "No write" and the summary-specific resource make the boundary reasonably clear.

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 implied by the scoping language ("in this Space", "optionally for a Campaign and since a Space sequence"), and the default-campaign behavior is stated. However, there is no explicit when-to-use vs. when-not guidance and no named alternative (e.g., catch_me_up or write_watch_summary) to route the agent.

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