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

Annotations already declare write (readOnlyHint=false), idempotent, and non-destructive; the description adds auth requirement, the fact that a timestamp is written, and concrete validation rules (FOUNDER needs product and bio, intro optional). It does not elaborate on the response or any side effects beyond the timestamp, so it stops short of full coverage.

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?

Dense but front-loaded: the login requirement and action come first, then validation, then error handling, then the chain. Bracketed markers impose structure without padding, though the terse clause stacking slightly reduces readability.

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?

With no parameters, no output schema, and annotations covering the safety profile, the description supplies the remaining essentials: precondition, validation gates, error behavior, and sequencing with get_onboarding_status. Nothing critical for correct invocation appears to be missing.

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 schema has nothing to explain and the baseline is 4. The description instead spends its words on preconditions and validation state, which is the right use of space for a parameterless action.

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: after confirmation it marks onboarding complete and writes a timestamp. It also names the sibling get_onboarding_status and clarifies this tool's distinct role in the flow, so an agent can separate it from status-reading siblings.

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 prerequisite (login required) and an ordered chain: get_onboarding_status → fill gaps → confirm → complete_onboarding. It also gives a when-not rule ('don't blindly retry on incomplete errors; fix first'), which is exactly the routing guidance an agent needs.

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