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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuine behavioral detail beyond that: sort order (overdue first), derivation rules for identity verification ('earliest among those not yet showing as verified'), the name-matching basis for the ICO fee register entry, and the presence of a calendar feed URL in the reply.

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-loaded with the core promise ('Every deadline a UK company has, sorted, with days left') and then dense enumeration; nearly every clause earns its place by naming a deadline source. The single long sentence is heavy but not padded.

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?

There is no output schema, so the description must carry the return contract, and it does: it enumerates the included deadline types, notes overdue-first ordering and the calendar feed URL. It stops short of describing the response shape, handling of companies with no deadlines, or behavior when a name matches multiple companies.

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?

Only one parameter and schema description coverage is 100% ('A company number, or a name'), so the schema already carries the semantics. The description adds nothing about the parameter itself — it does not restate that a name or number is accepted, nor address how ambiguous names are resolved. Baseline 3 for a single fully documented parameter.

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 resource (every deadline a UK company has) with scope and ordering, then enumerates exactly which deadline classes are covered: accounts, confirmation statement, director/PSC identity verification, ICO fee, payment practices and gender pay gap. This lets an agent distinguish it from siblings like gender_pay_gap or payment_practices, which it implicitly aggregates.

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: it is clearly the tool for a consolidated deadline view of one company. There is no explicit when-to-use guidance relative to the sibling report tools (e.g., whether to call this or gender_pay_gap/payment_practices for a single report), and no exclusions or prerequisites noted.

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