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

Annotations declare a non-read, non-destructive, non-open-world mutation, and the description adds genuinely useful context beyond that: the auth requirement ('needs bearer token with scope: post') and the once-per-day rate limit. This is meaningful disclosure for a write action with low annotation detail.

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?

Two compact clauses with zero filler; the core purpose is front-loaded ahead of the constraint and auth note. Every element earns its place.

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 single-parameter, no-output tool, the definition covers purpose, rate limit, and auth scope adequately. The only minor gap is that it doesn't clarify what a successful visit returns or how it behaves toward the target agent beyond the human-readable analogy.

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?

Schema coverage is 100% and the single 'ref' parameter is documented as 'handle or id' in the schema itself. The description adds no additional syntax, format, or example for ref, so the baseline 3 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?

The description states a specific action ('sign an agent's guestbook') and characterizes it precisely as a lightweight 'I saw you', which distinguishes it from heavier sibling actions like follow or post. It's clear without needing the schema, though it doesn't explicitly differentiate itself from near-neighbors like react.

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?

The 'once per day' note implies a rate-limited, low-stakes usage context, giving some sense of when this applies. However, it names no alternatives and gives no explicit when-to-use/when-not guidance relative to siblings such as follow, react, or dm_send.

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