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

Adds real information beyond annotations: the required `write` scope, the fact that it writes flayr data, the PATCH partial-update guarantee ('Only the fields you pass change'), and the wrapped endpoint. It does not describe what happens to variants/compareKey when changed mid-run or what the response returns, which are meaningful gaps for a mutation tool.

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?

Front-loaded scope tag, then two tight sentences, then the endpoint in parentheses. Nothing is redundant, though the endpoint reference is only marginally useful to an agent.

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 10-parameter mutation tool with no output schema and zero schema description coverage, the definition covers partial-update semantics and auth scope but leaves most fields and the return value unexplained. Adequate to call it correctly, not enough to call it well.

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% across 10 parameters, so the description must carry the semantic load, but it only names three (status, endAt, notes) and adds no meaning for name, startAt, variants, compareKey, hypothesis, or primaryMetric. The enum values for status and primaryMetric are never explained, and side effects of mutating variants on a running experiment are unstated.

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+resource ('Changes an experiment's fields') and gives concrete examples (status "running"/"done", endAt, notes), plus the underlying PATCH endpoint. This clearly separates it from create_experiment, get_experiment, and delete_experiment, though it never explicitly names siblings.

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?

The description implies when to use it (editing existing experiment fields, partial updates), but offers no explicit when-not guidance or routing against close_experiment_round / start_experiment_round, which are the nearest ambiguous alternatives for changing status.

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