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

Annotations already declare the mutation profile (readOnlyHint=false, openWorldHint=true, idempotentHint=false). The description adds value the annotations don't: the Ed25519 signing requirement on the envelope and the returned receipt id, both of which affect how an agent must construct and follow up the call.

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 tight sentences, front-loaded with purpose and return value, followed by the alternative and use condition. No filler or repetition.

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?

With no output schema, the description correctly states the return (receipt id) and the signing prerequisite. It stops short of describing failure modes (e.g. invalid signature) or what the receipt can be used for, but nothing essential for invoking the tool is missing.

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%, so the envelope's type and required action (proposal.submit) are already documented. The description only restates that the proposal is signed, adding no syntax, format, or field-level detail beyond the schema. 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?

Specific verb (submits) + resource (Ed25519-signed improvement proposal) + destination (Livre des IA) + return value (receipt id). This clearly separates it from siblings like get_ai_book or post_need, which operate on different resources.

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?

Explicit 'Use when: you want to propose an improvement to Faceabot' plus a named browser alternative for one-click signing. It lacks an explicit when-not condition, but the condition for use and the alternative path are both stated.

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