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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds meaningful context beyond them: no account, no key, no lead capture, and that the snippet is returned already assembled with the site's name and colour. It omits any rate-limit or side-effect detail, so not a 5.

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 core point is front-loaded, but the message is redundant: 'no account, no lead capture' and 'no account or key' restate the same idea, and 'one script tag' appears twice in consecutive sentences. Tightening would lose nothing.

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?

With no output schema, the description usefully discloses what comes back ('the answer comes back with `snippet` already assembled') and confirms there are no required params. Annotations carry the safety profile, so the remaining coverage is adequate, though return shape could be slightly more explicit.

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%, so the schema already documents url, brand, color, and theme — the baseline is 3. The description only gestures at brand ('your name') and color ('your colour') and adds no format guidance beyond the schema's 'hex' hint.

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?

States a specific resource (the embeddable widget snippet) and what it produces — an assembled one-script-tag snippet — which is clear enough to distinguish from read siblings like get_audit or audit_url. It does not explicitly name a sibling it differs from, so it stops short of a 5.

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?

It tells the agent to 'send the same query you would send to /embed', which implies the calling context, but gives no when/when-not guidance and never references an alternative MCP tool. Usage 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.