Register operator email (opt-in)

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

Beyond annotations (readOnlyHint=false, idempotentHint=true, etc.), the description adds the critical consent-based nature and the effect of attaching history to a real Fidacy account. It also preemptively clarifies side effects by stating it does not create an account or move money, which is valuable behavioral context.

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 two sentences, front-loaded with purpose, then a clear consent condition, and final exclusions. Every sentence earns its place with no redundancy.

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 simple one-parameter, opt-in tool with an output schema and annotations, the description covers purpose, usage conditions, and non-goals. It is fully self-contained and sufficient for an agent to invoke it correctly.

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% for the single parameter, and the schema already explains 'The operator's email, exactly as they gave it.' The description adds no new technical format or constraints beyond reaffirming it is the operator's email, so baseline 3 is appropriate.

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?

The description clearly states the specific action: 'Register the operator's email' and explains its purpose (so protection history attaches to a Fidacy account and Fidacy can reach them). It also explicitly distinguishes itself from creating an account or moving money, which differentiates it from siblings.

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?

Provides explicit when-to-use guidance: 'ONLY call this when the human operator has explicitly given their email and agreed to be contacted.' It also clarifies what it does not do (does not create an account or move money), helping the agent avoid misuse.

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