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

Annotations only declare idempotentHint=true and destructiveHint=false; the description adds real behavior beyond that — a write of the completion timestamp, persona-conditional requirements (FOUNDER needs product and bio, intro optional), and that validation failure returns an error rather than silently completing.

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 and front-loaded — completion semantics first, then validation rules, then workflow. The arrow-chain shorthand is efficient but sacrifices some readability, and the leading '登录;' fragment adds little.

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 parameterless state-transition tool with no output schema, the description covers prerequisites, validation gates, error handling, and the correct call order. What happens to the returned payload is unspecified, but that is minor here.

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?

Zero parameters, so there is nothing to document and the schema coverage is vacuously complete. The persona preconditions mentioned are context for failure modes, not inputs, so baseline 4 applies.

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: mark onboarding complete and write a completion timestamp, with persona-based validation rules. It distinguishes itself from the sibling get_onboarding_status by assigning that tool the read/inspect role. Slightly cryptic opening ('登录;') blurs the first clause.

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 ordered workflow: get_onboarding_status → fill gaps → confirm → complete_onboarding, plus a clear negative instruction not to blindly retry on incomplete-data errors. No explicit exclusion cases, but the sequencing is unambiguous.

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