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

Annotations already declare a non-idempotent, non-read-only, closed-world mutation. The description adds real value on top: auth requirement, the fact that it returns grounds/confidence/route/deadline, and the conditional behavior that empty observed_notes yields only general grounds and a 'possible appeal' rather than money owed. It does not contradict any annotation, though duplicate/idempotency handling is left unaddressed.

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?

Three sentences, each carrying distinct information (action, return payload, matching logic/caveat). It is front-loaded onto the core action and avoids padding, though the middle sentence packs several return fields into one dense clause.

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?

With 17 required parameters, no output schema and no nested objects, the description does the necessary work: it discloses the authentication requirement, summarizes the return payload, and explains the conditional outcome when observed_notes is empty. Only edge cases such as duplicate submissions are left uncovered.

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 100%, so the schema already documents all 17 parameters thoroughly, making 3 the baseline. The description does add one meaningful point of semantics — that grounds are matched against contravention, location and observed_notes — which explains how the inputs are consumed, but it does not otherwise elaborate on parameter syntax or formats.

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 (adds) and a precisely scoped resource (a UK council PCN or private parking charge) and names the secondary effect (runs the appeal-grounds engine). This cleanly separates it from the other add_* record tools, which cover flights, trains and TfL journeys.

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 rather than stated: an agent can infer this is for recording a parking ticket someone received. The description adds a useful prerequisite (Untap sign-in) and a conditional caveat about missing observed_notes, but it names no alternative tool or explicit when-not case.

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