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

Annotations declare a non-read-only, non-idempotent, open-world call, and the description usefully adds the concrete side effect the annotations cannot: the connection is moved onto the free plan with a 50,000 requests/month quota. Missing is failure behavior (invalid/expired code) and whether the operation can be repeated safely.

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?

One sentence, front-loaded with the verb and resource, with the quota consequence attached rather than buried. No filler or redundancy.

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 one-parameter mutation with no output schema, the description covers what happens on success but not the workflow context an agent needs: ordering relative to aura_claim_email, behavior on an invalid code, and what the tool returns or whether the plan change is reversible.

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 parameter is already documented as "The 6-digit code the user received." The description restates the 6-digit, emailed nature of the code without adding format, validation, or sourcing detail beyond the schema, 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?

States a specific verb and resource ("Checks the 6-digit code from the user's email") plus the resulting state change (free plan, 50,000 requests/month). It is clearly distinct from aura_upgrade by naming the free tier, but it never explains its relationship to aura_claim_email, which is the likely prerequisite step.

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?

Usage is only implied: an agent can infer this is the step after the user receives a code, and that it enrolls the connection on the free plan. No explicit when-not guidance, no mention that aura_upgrade is the alternative for a paid tier, and no stated prerequisite that an email must be claimed first.

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