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

Annotations cover readOnlyHint=true, and the description adds genuinely useful context beyond them: it is static instructions only, returns no account data, and the agent cannot create the credential itself. It does not describe pagination/format, but for a static help tool this is solid disclosure.

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?

Three tight sentences with the returned content front-loaded and the usage trigger second; no filler. The first sentence is dense but every clause (sign-in route vs. token fallback) carries information an agent needs.

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?

No output schema exists, and the description adequately characterizes the return (the browser sign-in route followed by the manual token procedure) without needing to enumerate structure. Combined with the no-account-data and agent-cannot-create notes, an agent has what it needs to answer and set expectations.

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 and the description has no parameters to explain. Per the rubric, zero-parameter tools baseline at 4; no parameter information is needed or missing.

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?

States a specific verb and resource: it returns the procedure for connecting a real account so account.* tools become available, and it names the exact outcome (browser sign-in first, manual API token as fallback). It reads distinctly from help.authStatus (status), but overlapping with help.startSignup is not explicitly addressed, so differentiation is strong-but-not-perfect.

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?

Gives an explicit trigger: 'Call this when a customer wants to manage their real banner and the account.* tools are not available.' That is a clear precondition, though it never names a competing sibling (e.g. help.startSignup) or states when not to use it.

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