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

The description discloses the side effect of sending an email and mentions the code's 10-minute TTL (from schema). It outlines the two-step process. No contradiction with annotations (readOnlyHint=false, destructiveHint=false). It adds behavioral context beyond annotations.

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 concise with four sentences, each providing essential information: what the tool is, what it does, the next step, and when to use it. No redundant or extraneous content.

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 two-step registration tool with a well-documented schema and existing output schema, the description covers the purpose, flow, and usage context. It could mention return values or error scenarios, but output schema exists, and the description is sufficient.

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 parameters are already well-documented. The description does not add new semantics beyond the schema; it only provides high-level context. 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 'Step 1 of agentic signup' and specifies the action: 'Sends a 6-digit verification code to the email.' It distinguishes the tool as the first step of a two-step process and explicitly names the next tool (register_organisation_verify). The resource and purpose are unambiguous.

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 this when a user wants to create a new FavCRM workspace from inside an MCP client.' It also outlines the subsequent step (call register_organisation_verify). It lacks explicit 'when not to use' but the context is clear enough for an agent.

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