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

Discloses non-obvious behavior annotations cannot: duplicates and below-threshold items are skipped, the owner is notified exactly once, and crucially a second run over the same period re-flags but suppresses a repeat notification. This idempotent-notification semantics is exactly the context an agent needs before re-running.

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 dense sentences, front-loaded with the core action and period default. The second sentence on repeat-run behavior is slightly awkward but earns its place by covering an important edge case.

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 write tool with no annotations beyond safety hints and no output schema, the description covers action, scope, threshold, notification, and re-run semantics well. It omits what the returned result or 'flag' state looks like, a minor gap.

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% with clear per-parameter descriptions (date defaults, threshold with R5,000 preset). The description reinforces threshold/duplicate behavior but adds no syntax or format detail beyond the schema, so baseline 3 is correct.

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 (flag) and resource (expenses with no slip/receipt attached), plus scope (a period). No sibling tool overlaps this action, so an agent can identify it immediately from name and description.

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?

Usage is implied by the purpose (chase expenses missing receipts) and the description gives a sensible default period, but it never states when to prefer this over another approach or any preconditions. Adequate but no explicit guidance or exclusions.

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