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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely non-redundant context: the required role (contributor/editor/owner) and the side-effect boundary that updated_at is untouched.

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 tight sentences, with the core action front-loaded and the role/side-effect caveats trailing. No filler.

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?

Auth and side-effect behavior are covered, and no output schema means return values need no explanation. However, for a three-parameter mutation with zero schema descriptions and no output schema, leaving every parameter undocumented is a real 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 0% and the description names none of the three parameters. The non-obvious idempotency_key (and its 8-200 char constraint) and the content limit go entirely unexplained, and 'dated' hints at a date field the caller cannot supply.

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 ('Add a dated comment to an experiment') and no sibling tool offers comment creation, so the agent can place it immediately. The parenthetical example ('an interim reading while the test is Running') further pins down intent.

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?

Gives a concrete usage scenario (interim reading during a running test) and implicitly separates itself from hypotize_experiment_update by noting it does not change updated_at. It stops short of naming an alternative tool or stating when not to use it.

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