List signals

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context: newest-first ordering, cursor pagination behavior, and the fact that system sources are included in filtering. It doesn't describe return shape or rate limits, but with readOnly annotations that burden is lighter.

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 efficient sentences that pack all the essential info: purpose, ordering, filters, and pagination mechanism. Zero waste or repetition of what the schema already documents.

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 listing tool with 71% schema coverage and good annotations, the description covers the important behavioral aspects (ordering, filters, pagination). It doesn't detail the return value format, but there's no output schema and this is a straightforward list operation, so a 4 is appropriate rather than a gap requiring higher effort.

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 coverage is 71%, and most params have useful descriptions. The description adds value by explaining that 'source' includes system sources (giving concrete examples rank_tracker and search_analytics), and clarifies that 'type' is an exact match. This goes beyond what the schema enum/pattern alone conveys.

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?

Specific verb (list) + resource (signals for a project) + clear scope (newest first). Explicitly names the filter dimensions (source, type, date range) and pagination, distinguishing it from sibling tools like list_traffic_snapshots and list_triggered_alerts which list different signal-adjacent data.

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 states ordering (newest first) and clearly explains the filtering capabilities including source, type, and date range via from/to. It explains that source includes system sources such as rank_tracker or search_analytics, which is helpful. However, it doesn't explicitly name alternatives or state when NOT to use this tool versus list_traffic_snapshots or get_rank_history, though the scope is reasonably implied.

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