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

Annotations already declare readOnlyHint=true, destructiveHint=false and idempotentHint=true, so the safety profile is covered. The description reinforces this with 'opens nothing by itself' and discloses the return shape (screens, buttons, fields) and the handoff to browser tools, which is real context beyond the annotations. Minor noise: an API availability note dated 14 Oct 2026, a future date, which reads as stale or templated.

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 sentences, front-loaded with what the tool returns and immediately followed by what the agent must do next. The trailing REST API sentence adds nothing an agent needs in order to call this tool and could be dropped; the audience phrase 'ChatGPT, Claude or any AI agent' is also 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 no-parameter, no-output-schema guide tool, the description covers what comes back and the follow-up path, which is what an agent needs. It could be tighter on coverage limits, for example which sevdesk screens the guide covers, but nothing essential is missing.

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 takes zero parameters, so the baseline is 4. The empty schema with additionalProperties false is consistent with the description, which correctly implies no inputs are needed.

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 states a specific resource (invoice in the user's sevdesk account) and, crucially, clarifies that the tool returns step-by-step instructions rather than performing the action: 'opens nothing by itself'. This separates it from action-performing siblings like sevdesk_create_invoice and cotlet_browser_click. It loses the top score only because the opening clause 'Send invoice...' still reads like an action verb before the clarification arrives.

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 workflow: call this to get the steps, then execute with the cotlet_browser_* tools in the Cloud Browser. That is actionable sequencing. It does not, however, say when to prefer this over sevdesk_create_invoice, which is the closest ambiguous sibling.

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