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

With readOnlyHint already declaring the safety profile, the description adds genuinely new behavioral context: the returned `instructions` are meant for the agent, not the end user, and `connect_url` is only populated while no Instagram account is connected. These handling and conditional-state details go beyond the annotations, though return structure nuances are left to the output schema.

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?

Front-loads what the tool provides, then the when-to-call condition, then handling caveats. Three sentences with no padding; the only minor inefficiency is that the connect-link detail trails after the usage guidance.

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 guide tool with an output schema, this covers purpose, trigger, and the two key output fields. Since the output schema exists it needn't explain return values exhaustively, but it could say a bit more about what the `instructions` contain or that the flow ends once Instagram is connected.

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 description still meaningfully characterizes the two notable output fields (`instructions` and `connect_url`), adding value even though there is no input to document.

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 verb+resource (welcome a new user / onboarding steps) and names the concrete artifacts returned (steps and an Instagram connect link), so an agent understands this is a guided-setup resource rather than an action. It doesn't explicitly contrast itself with the closest sibling, connect_instagram, but the purpose is unambiguous.

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 explicit triggering conditions: call it the first time a user uses Saypage, or when they ask how to start or what Saypage can do. That is clear when-to-use guidance, though it names no when-not conditions or alternative tools.

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