list_metrics

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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety profile is covered. The description adds genuinely new behavioral context by warning that returned training content is untrusted data, not instructions, and by naming the fields returned (stream, point counts, last steps), which the annotations do not convey.

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 no filler; the field list is front-loaded and the prefix example is concise. The untrusted-data warning is slightly appended but is substantive enough to earn its sentence.

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 and low parameter coverage, the description should do more to clarify pagination and the meaning of search/uid beyond what uid's schema note provides. It adequately covers return-content shape and untrusted-data handling, but an agent still lacks guidance on result size and traversal.

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 only 20% (essentially just uid), so five parameters must be explained largely by the description. It hints at the stream dimension and prefix grouping, but says nothing about limit/offset pagination or what 'search' filters on, leaving most parameters undocumented in either place.

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 pairs a specific verb ('Discover') with the concrete resource ('scalar metric keys, stream, point counts and last steps'), so an agent knows this lists metric metadata rather than values. It does not name a sibling, so the boundary with get_metric_series/get_history must be inferred from the word 'Discover'.

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?

There is no explicit statement of when to use this tool versus get_metric_series, get_history or plot_metric. The slash-prefix sentence describes data shape ('train/', 'eval/') rather than a usage condition, leaving the agent to guess the listing-vs-fetching split.

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