reply_all_email

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

Annotations already indicate destructiveHint=true. The description adds behavioral context such as 'Immediately reply', 'Threading headers (In-Reply-To, References) are preserved', and 'Requires PROTONMAIL_ALLOW_SEND'. These details go beyond annotations and are useful for the agent.

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 three sentences, front-loaded with the main action. Every sentence contributes essential information: action, relation to sibling, usage guidance, and behavioral details. No wasted words.

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?

Given the tool's complexity (12 parameters, no output schema), the description covers the core purpose, usage guidance, and key behavioral traits. It mentions required permission and threading preservation. While it does not describe return values or error scenarios, the schema covers parameters, and the description is sufficient for tool selection.

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%, meaning each parameter already has a description. The tool description does not add significant new meaning for parameters beyond what the schema provides. The baseline is 3, and the description makes no extra parameter clarifications.

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 tool replies to all original recipients (sender + To/CC) of an existing email, and distinguishes itself from reply_to_email by specifying it is identical with replyAll enabled. The verb 'reply' and resource 'email' are explicit.

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?

The description explicitly says 'Use when the conversation involves multiple parties and all should receive the reply,' providing clear guidance. It implies not to use when only the sender needs a reply, but does not name the alternative tool directly aside from stating it is identical to reply_to_email with replyAll enabled.

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