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

Annotations already declare non-read-only, non-idempotent, destructive behavior, so the bar is lower; the description adds a genuine auth prerequisite (the assistant switch) that isn't in the structured data. It doesn't say whether the write overwrites the prior range outright, which would round this out.

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?

Two tight clauses with no padding; the mutating action and the target field are front-loaded before the prerequisite. Every element earns its place.

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 two-parameter mutation with no output schema, the description covers scope, units, and the precondition, while annotations carry the safety profile. The main residual gap is not stating the effect on any pre-existing range or the return behavior, but that is minor here.

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% – both parameters already document units and bounds (max capped at 100000, min >= 0, max >= min). The description only restates 'GBP, min and max', adding no syntax or constraint detail beyond the schema, so the baseline 3 applies.

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 precise verb+resource: updating the member's own public fee range (GBP min/max) on their profile. The parenthetical '(GBP, min and max)' and 'the same field as the app's profile editor' disambiguate it from read-only siblings like get_rates and profile setters like set_my_bio/set_my_availability.

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?

Clearly scopes usage to the member's own profile and states the operative precondition ('Allow my assistant to act' switch), which is exactly the kind of context that routes invocation. It stops short of naming an alternative (e.g., get_rates to inspect current values) or an explicit when-not-to-use, so it isn't a full 5.

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