pmus_list_markets

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context: the flat (non-grouped) response shape and the unreliability of the eventSlug filter. It doesn't describe pagination or response format, but the output schema exists and the annotations carry the safety burden, so a 4 is appropriate.

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 sentences with no filler. The primary behavior is front-loaded, and the alternative recommendation is placed second. Every word earns its place.

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 read-only list tool with an output schema and rich annotations, the description covers the key decision point (flat vs. grouped) and the known pitfall (eventSlug filter). It doesn't mention pagination or default ordering, but those are partially encoded in the schema defaults. The only real gap is that it doesn't explain what 'flat' means in terms of the response structure, but the output schema likely covers that.

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%, so the description carries no parameter-level detail. However, the schema itself is fairly self-explanatory (limit, active, closed, offset, category, order_by, order_direction, description_chars) with defaults and constraints. The description adds no parameter semantics beyond the schema, so the baseline 3 applies.

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 states a specific verb ('List') and resource ('markets'), and immediately clarifies the flat vs. grouped distinction. It also names the preferred alternative (pmus_get_event) for event-specific markets, which distinguishes it from sibling tools without needing to inspect schemas.

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 explicitly says when to use this tool (for a flat list of markets) and when not to (for an event's markets, prefer pmus_get_event). It also warns that the gateway's eventSlug filter is unreliable, which is a concrete exclusion that helps an agent avoid a known failure mode.

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