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

Annotations already signal that the tool is not read-only and not destructive. The description adds useful behavioral context: the screenshot is generated server-side from the stored website, the client needs one configured, and the new URL is returned. There is no contradiction with the 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?

Two compact sentences front-load the core action and return value, then add context and the usage trigger. Every sentence earns its place with no filler.

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 one-parameter mutation with an output schema, the description covers purpose, prerequisites, usage timing, and return value. An agent has what it needs to select and invoke the tool correctly.

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 only parameter is clearly documented as 'Client ID (from list_clients)'. The description adds no parameter-specific semantics, so it sits at the baseline 3.

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 opens with a specific verb ('Re-take') and resource ('screenshot of a client's website'), and states the return value (the new URL). This makes it immediately distinguishable from sibling refresh tools like refresh_client_favicon or refresh_report.

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 gives an explicit trigger condition: use this when the site has changed and the card looks stale. It also notes a prerequisite (the client must have a configured website). It does not mention sibling alternatives or explicit when-not-to-use scenarios, so it stops short of a 5.

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