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

The annotations already flag destructiveHint=true, and the description earns credit by explaining exactly what is destroyed: the previously saved text for that field, with no retention. It adds the partial-update semantic ("Only the fields provided are changed") and a user-confirmation requirement that annotations cannot 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?

Four short sentences, each carrying distinct information: what it replaces, the irreversibility warning, the downstream scoring impact with a brevity constraint, and the sibling alternative. The destructive behavior is front-loaded before the routing advice.

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, no-output-schema mutation with a low-complexity surface, the description covers scope, overwrite risk, partial updates and alternatives. The only real gap is what an empty or omitted-versus-empty value does, which matters for a destructive setter.

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%, so both parameters are already documented, but the description adds meaning beyond the schema: that omission of a field leaves it untouched and that each value should be kept to a sentence or two. It does not clarify whether an empty string clears a field, which limits it to a 4.

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?

"Replace how the account positions itself and who it sells to" gives a specific verb (replace) and resource (positioning/ICP), and the closing sentence explicitly contrasts it with add_context_note, which adds rather than overwrites. An agent can distinguish this tool from its siblings without opening the schema.

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?

It names the alternative tool (add_context_note) and the exact condition that routes to it: free-form facts like roadmap, pricing changes or customer comments. It also states the when-not condition implicitly by saying the old text is not kept, so confirmation is required.

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