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

No annotations provided, so description carries full burden. Discloses that the flow is human-in-the-loop, sends a welcome DM requiring manual reply, and that receive_credentials calls destructively drain the relay mailbox. Warns against polling or retrying.

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?

Description is concise at 8 sentences, each adding value. Structured with purpose, comparison, caveat, flow detail, and explicit instructions. No fluff or 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?

Covers all necessary aspects for a credential-delivery tool with human-in-the-loop: what it does, when to use alternative, post-call actions, and warning about destructive drain. Output schema exists to handle return value details.

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% with existing descriptions indicating 'Required' and source tools. The description does not add significant meaning beyond the schema; both parameters are already well-documented in the input schema.

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's purpose: 'Open a Secure Courier channel for credential delivery.' It specifies the resource (credential channel) and action (open), and distinguishes from sibling tool 'request_npub_proof' by contrasting use cases.

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?

Explicitly states when to use this tool vs alternatives: 'To merely prove you control an npub, use request_npub_proof instead.' Also advises checking service_status for dynamic/OAuth2 services. Provides clear post-call instructions: 'After calling this tool, STOP and tell the user what to do. Wait for the user to confirm...'

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