list_metrics

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

The description goes well beyond the readOnly/idempotent annotations by stating 'Mode: disabled' and 'calls return AUTH_REQUIRED without retrieving data,' which is critical for an agent deciding whether/how to invoke it. It also discloses that IDs are namespaced per service and must not be merged. No annotation contradiction.

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?

The tool's purpose is front-loaded and every sentence carries information. The disabled/research sentences are slightly choppy and redundant ('Mode: disabled' plus 'Research is disabled'), but the description remains efficiently packaged.

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 simple metadata-listing tool, the description covers purpose, symbol semantics, ID namespacing, and auth failure behavior, with an output schema covering return shape. The gap is that the valid namespace enum contradicts the broader service list in the description, which an agent would need clarified to call the tool correctly.

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?

With schema coverage at 50%, the description compensates partially by explaining symbol=null for market-wide services and by stressing service-namespaced IDs. But it references service names absent from the namespace enum and stays silent on page semantics, so the added value is real but imperfect.

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 opening sentence states a specific action and resource: 'Discover metric metadata without numeric values,' which clearly differentiates it from a numeric statistics tool like get_key_statistics. However, the description then lists financials, fundachart, and comparison as supported service scopes even though the namespace enum only allows keystats and screener, so the scope is slightly muddled.

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 gives useful context for when to pass a symbol vs null ('keystats and financials require a symbol; screener, fundachart and comparison are market-wide'), and it notes the tool is disabled with calls returning AUTH_REQUIRED. It never explicitly contrasts this tool with its siblings search_companies or get_key_statistics, nor says when to prefer another tool.

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