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

The annotations declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, and the description reinforces this by saying it 'opens nothing by itself' and returns step-by-step instructions (screens, buttons, fields). It adds context the annotations cannot express — the nature of the return value and that execution happens elsewhere — but says nothing about the guide's scope limits or how it stays in sync with the UI.

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 operational content is front-loaded in the first two clauses, which is good. The trailing sentence about Zammad's REST API and the absence of an official MCP server (with a checked date) is justification/marketing rather than invocation guidance and does not earn its place in a tool definition.

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?

Given zero parameters and no output schema, the description does well to say what comes back (step-by-step screens, buttons, fields) and what to do next. The notable gap is that it never says how the agent identifies which tickets to merge, nor which cotlet_browser_* tool to invoke first, so an agent must infer the handoff.

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 with additionalProperties=false, so there is nothing for the description to disambiguate at the schema level; the baseline for a parameterless tool applies. The description does not need to explain arguments, though it also does not explain how the target tickets are conveyed to the guide.

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 names a specific verb and resource ('Merge tickets in Zammad') and immediately disambiguates the kind of tool it is: it 'Returns how to do it in Zammad step by step... and opens nothing by itself.' That negation prevents the agent from mistaking it for a mutation tool, which is the main confusable reading of the name.

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 clearly states the usage path: call this to get the procedure, 'then do it with the cotlet_browser_* tools in the user's Zammad Cloud Browser.' It does not name a specific browser tool to start with (open vs. navigate vs. click) or state when the guide is unnecessary, so guidance is strong but not fully closed.

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