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

Annotations already declare destructive=true, idempotent=true, openWorld=false; the description corroborates rather than contradicts and adds boundary context (it records a URL but does not fetch it, and does not touch published pages). It stops short of stating what a replace destroys or any permission requirements.

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?

Two tight sentences with no waste: the action and inputs come first, then the explicit boundaries. Every clause earns its place.

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 rich annotations, 100% schema coverage, and no output schema, the description supplies everything an agent needs to call it correctly: what it stores, required inputs, and what side effects it will not produce. Only the update-in-place consequence of reusing a name is left solely to the schema.

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%, and the schema already explains the picker handle, the source URL and the markdown content. The description only names the inputs generically, adding no format or constraint detail beyond the schema, so the baseline 3 applies.

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 verb (save/replace) and resource (named design guide) plus the inputs (markdown, source URL) and what it stores (typography, colour, layout rules). It is clearly distinguishable from delete_guide by action, but never names or contrasts with sibling brand_guide, so sibling differentiation is only implicit.

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?

Gives explicit negative guidance on when this is the wrong tool: 'Does not visit the source URL, extract website assets or change published pages.' That steers an agent away from assuming crawling/publishing behaviour, though it does not name an alternative tool to use for those cases.

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