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

With no annotations, the description carries the behavioral disclosure burden. It reveals the return shape ('titles with timestamps and edit comments') and how parameters affect results ('Pass topic to filter and hours to widen the window'), going beyond the schema. It does not discuss edge cases like empty results or ordering, preventing a higher score.

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 description is three sentences, front-loaded with the core purpose ('What changed in the last hours or days') and no wasted words. Each sentence serves a distinct role: what, when, and how.

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 tool with no output schema, the description adequately covers the return format and usage guidance. It lacks details on ordering or empty results, but the schema already documents parameter constraints, making this a solid 4.

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 100%, so the baseline is 3. The description adds meaningful context for two parameters: topic ('filter') and hours ('widen the window up to a week'), while limit is left entirely to the schema. This extra guidance justifies a 4.

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 clearly identifies the tool as returning recent changes: 'What changed in the last hours or days' and 'Returns titles with timestamps and edit comments.' It also distinguishes from siblings by positioning itself as the 'escape hatch' for facts newer than the training cutoff, implying other tools handle different lookup scenarios.

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?

It provides explicit trigger conditions: 'Reach for this whenever the answer could have moved since you were trained' with concrete examples (elections, appointments, acquisitions). It does not explicitly name a direct alternative tool like search, but references lookup() for follow-up, so it falls short of a 5.

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