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

No annotations are provided, so the description carries the full burden. It does well: it discloses the behavior (typed, identified, ticketed, human-signed), the routing (x-gsc-inbound address), and explicitly states a limitation ('No new write path here'). It even explains the relationship to the transaction MCP. This is solid transparency for a zero-parameter tool.

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 sentences, all of which carry meaning. The purpose is front-loaded, and the necessary qualifiers (no new write path, human-signed) are packed tightly. The only slight redundancy is the title-phrasing ('agents' door') which adds little, but the description itself is efficient and skimmable.

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 zero-parameter tool with no output schema and no annotations, the description fully explains the service being exposed, its interaction model, and its constraints. An agent can understand how to use it, where it routes, and what it does. Missing details like exact payload syntax and response format are acceptable given the absence of parameters and the nature of the tool as a policy statement rather than a function call.

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?

The tool has zero parameters, so the schema covers 100% of nothing and imposes no burden on the description. The description doesn't need to document any parameters, and it doesn't attempt to. It does mention the message types (RFQ, terms request, escalation) which gives the agent context on how it would be used, effectively compensating for the absence of a structured envelope.

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 is specific about the tool's purpose: it describes how an agent lodges specific message types (RFQ, terms request, escalation) with a specific identified recipient (GreenCore Solutions Corp), using a specific protocol (IA-MESSAGE). It clearly distinguishes itself from the sibling tools by noting it 'points at the existing door' rather than being a new write path, and the sibling list contains no other messaging tools.

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 gives clear context on what the tool is for (lodging typed, ticketed, human-signed messages) but doesn't explicitly state when to use this versus alternatives. There's no guidance on when NOT to use it, though the note 'No new write path here' and pointing to the x-gsc-inbound address and transaction MCP imply outside the normal flow. Without explicit alternative names or conditions, the guidance is implied rather than stated.

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