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

Annotations already declare a non-read-only, non-destructive, non-idempotent, closed-world mutation, and the description adds the meaningful consequence that it 'completes the session on their account' — a state change beyond the raw annotation flags. It does not mention what happens on repeat calls or what a completed session blocks, so idempotency implications remain implicit.

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?

One dense sentence front-loads the action, the scale, and the account-level effect with no filler. The clause stacking ('the same post-session check-in the app asks: a 0-9 answer to the experience's feedback question') is slightly convoluted but still parses cleanly.

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 two-parameter tool with full schema documentation and no output schema, the description covers what is recorded, the scale, and the completion side effect. The only gap is the absence of any note on repeat submissions given the declared non-idempotent behavior.

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 both parameters are already fully documented, including the 0-9 anchors and the sessionId pattern. The description restates the scale rather than adding new meaning beyond the schema, which is the baseline case for a fully documented parameter set.

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?

States a specific verb and resource: recording the user's post-experience feeling on a 0-9 scale, plus the side effect of completing the session. It is immediately clear what the tool does, but it does not explicitly differentiate itself from siblings that also finalize state, such as complete_journey or complete_today_feed.

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?

Timing is clear: it is the post-session check-in asked after a Reulay experience, and the schema ties sessionId back to start_experience. There is no explicit statement of when not to call it or which sibling to prefer if the user has not just finished an experience, so it stops short of full routing guidance.

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