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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description reinforces this with 'opens nothing by itself', preventing the agent from assuming the reply is actually sent. It also discloses the return shape (steps with screens, buttons, fields) and adds context that Trengo has a REST API but no official MCP server, explaining why browser automation is needed. Auth/prerequisite state of the Trengo Cloud Browser is not covered.

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 carry the operative meaning and are well ordered: what it returns, then what to do next. The opening restatement of the title and the ChatGPT/Claude/any-AI-agent clause are somewhat padded, as is the API-background sentence, though the latter earns its place by justifying the browser route.

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 zero-parameter, no-output-schema guidance tool, the description covers purpose, return content, side-effect profile and the follow-up tool family, which is nearly everything an agent needs. The remaining gap is prerequisite state: whether a Trengo Cloud Browser session must already be open or authenticated before the returned steps can be followed.

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; no parameter semantics are needed or missing. The description correctly adds nothing about inputs and instead spends its space on output and execution path.

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 resource (Trengo customer replies) and states the actual output: step-by-step instructions covering screens, buttons and fields. It also implicitly distinguishes itself from the cotlet_browser_* tools by saying it 'opens nothing by itself'. The opening clause 'Reply to customer...' duplicates the title before being corrected, which slightly blurs whether the tool acts or advises.

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 follow-up path: get the steps here, then execute with cotlet_browser_* in the user's Trengo Cloud Browser. What's missing is explicit exclusion versus Trengo siblings such as trengo_add_internal_note or trengo_read_a_conversation, i.e. which Trengo task maps to which tool.

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