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

Annotations only cover the safety profile (readOnly=false, openWorld=true, idempotent=false); the description adds genuinely new behavioral context — third-party data sharing, a possible referral fee, and the success signal ('Returns ok true when sent'). It does not describe failure behavior or whether data is retained, so it stops short of a 5.

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 short sentences with no filler; the disclosure of third-party sharing is front-loaded ahead of the call precondition and the return value, which is the right ordering for an agent deciding whether to invoke.

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 mutation tool with full annotation coverage, a complete schema, and no output schema, the description covers purpose, consent precondition, third-party disclosure, and return shape. It omits error/failure behavior and retry semantics, which keeps it from being fully complete.

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% with 10 well-documented parameters and three enums, so the schema carries the parameter burden and baseline 3 applies. The description only indirectly echoes the consent_to_share requirement ('agreed to share these details') and adds no syntax or format detail 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?

States a specific verb and resource ('sends the user's site details to UK Charging Solutions') and names the downstream recipient, so an agent can instantly tell this submission tool apart from the read-only calculator/fact siblings. The side effect (possible referral fee via an installer partner) is stated up front.

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?

Gives an explicit gating condition: 'Only call this when the user asked to be contacted and agreed to share these details.' That is a clear when-to-use rule, though it never names an alternative tool (e.g. host_income_estimate) for users who are merely exploring rather than requesting contact.

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