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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful framing — it returns instructions and 'opens nothing by itself,' and explains the absence of a public API — but it doesn't describe the shape of the returned steps or any limits on their fidelity.

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 core guidance (returns steps, opens nothing, use cotlet_browser_* next) is front-loaded, but the trailing sentence about 404s on specific URLs and the QuickBooks FAQ note is verbose and reads more like research provenance than invocation guidance. It could be trimmed without losing meaning.

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, read-only guidance tool with no output schema, the definition covers what it returns (screens, buttons, fields), the handoff to browser tools, and the rationale for using a browser rather than an API. Sufficient to call correctly, though it omits how to interpret or act on the returned steps when they don't match the live UI.

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. Schema coverage is 100% with an empty object schema, and nothing in the description needs to compensate for undocumented inputs.

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 the specific resource ('Message Log in the user's own EZ Lawn Biller account') and explicitly says it returns step-by-step instructions rather than performing the action. It's clear what the tool does, though it doesn't explicitly differentiate from siblings like ez_lawn_biller_activity_log or ez_lawn_biller_billing_history, which an agent could confuse it with given the large catalog.

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 a clear two-step workflow: this tool returns the how-to, then the agent executes with cotlet_browser_* tools in the Cloud Browser, and it notes it 'opens nothing by itself.' That is strong operational context, but there is no explicit when-to-use/when-not versus the other log/history siblings.

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