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

With no annotations, the description carries full responsibility for behavioral disclosure. It does reveal default fallback behavior and lists the stages of the calculation, but it is silent on whether the operation is read-only, any side effects, error conditions, or authentication needs. For a calculator, non-mutation is fairly implied, but not stated explicitly.

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?

A single sentence that front-loads the action and resource and then lists all outputs compactly. The only blemish is the redundant phrase 'calculator ... calculator' (the tool name/title already includes it).

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?

The description defines what the tool returns (chargeable gain, relief-rate tax, 24% tax, total CGT), and the schema covers all inputs, so an agent has enough to call it correctly. It lacks explicit usage conditions or error/edge-case notes, but given the simplicity of a calculator these are not critical gaps.

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?

The input schema covers all five parameters with descriptions (100% coverage), so the baseline is 3. The description's only param-related note is that missing inputs fall back to documented defaults, which adds a general behavior but no per-parameter meaning beyond 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?

Description opens with the verb 'Run' and names the specific resource 'Exit proceeds calculator (2026/27)'. It enumerates the computed outputs (Chargeable gain; Tax at 18%; Tax at 24%; Total CGT), which clearly sets it apart from the sibling 'calculator_describe' that likely only describes the calculator.

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?

The description implies usage when one needs to compute exit-proceeds tax figures, and it notes default fallback behavior, but it does not explicitly state when to prefer this over 'calculator_describe' or the enquiry tools, nor any conditions where it should not be used.

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