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

The description transparently explains the data source (2026 estimates, published averages, rounded), that means-test notes are educational only, and deliberately avoids a 'how much could you protect' computation. This adds behavioral context beyond what annotations (none provided) would typically convey.

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 a single, well-structured paragraph that front-loads the main purpose and efficiently covers data source, computation, and educational caveats. Every sentence contributes distinct value.

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 tool with 3 parameters and no output schema, the description adequately explains the computation model, included notes, and what is deliberately omitted. It does not specify the exact return format, but the overall purpose and behavior are clearly conveyed.

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 brief descriptions. The tool description adds value by explaining how parameters feed into the formula (years × 52 × weekly ranges) and provides context for the weekly ranges (typical self-funder, sourced 2026 estimates). This enriches meaning beyond the basic 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 clearly states 'Project what care home fees could cost' with specific computation details (weekly ranges × 52 × years, by region and care type). This distinguishes it from siblings like calculate_iht or check_deed_of_variation.

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 through the description's focus on projecting care costs for self-funders, but there is no explicit guidance on when to use this tool versus alternatives, nor any exclusions.

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