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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, covering the safety profile. The description adds the signal semantics and lifecycle fields, but that content overlaps with the existing output schema, so it adds only modest context beyond structured data.

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-loads the purpose, then gives a compact argument list with per-parameter notes. No filler sentences; slightly list-heavy but efficient.

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 two-parameter read-only list tool with annotations and an output schema present, the description covers purpose, signal domain, lifecycle output and both parameters. The remaining gap is sibling disambiguation and limit semantics, which are minor here.

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 schema documents nothing. The description usefully enumerates the status values (open/resolved/all) which the schema lacks as an enum, but limit is only restated as '最多返回条数' with no range or default guidance, and its default of 50 is left to the schema.

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 and resource ('列出已检测到的变化信号'), names the signal domain (visibility 提升/退化) and mentions lifecycle fields. An agent understands it lists detected change signals, but there is no explicit differentiation from siblings like diff_observations or score_visibility.

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?

No statement of when to use this tool versus the six siblings, nor any prerequisites or exclusions. The only guidance is implicit in the status values, which describe filtering rather than when to prefer this tool.

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