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

The annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered by structured data. The description adds useful context about what comes back (senders, subjects, extracted summaries), but says nothing about ordering, result limits, truncation, or whether message bodies are included — gaps that matter when openWorldHint signals live external data.

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?

A single well-formed sentence that front-loads the action and scope, then lists the returned fields without any filler or redundancy. Nothing can be removed without losing information.

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 simple two-parameter read tool with full schema coverage and no output schema, the description is nearly sufficient: it names the fields returned, which compensates for the missing output schema. The remaining gap is volume/ordering behavior of the listing, which an agent might want to know before calling.

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 description coverage is 100%, so both parameters (token, address) are already documented, and the description adds no syntax, format, or validation detail beyond them. The phrase "owned with the supplied token" only restates the token's provenance already stated in the schema, so the baseline of 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 uses a specific verb and resource ("List messages in a temporary inbox") and scopes it to an inbox owned by the supplied token, so an agent knows exactly what the call does. It is distinguishable from gecici_create_inbox and the wait_* siblings, though it does not explicitly name them or contrast with gecici_get_ai_summary, which also surfaces summaries.

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: the phrase "owned with the supplied token" hints that this runs after gecici_create_inbox, but no alternative tool is named and there are no when-not-to-use conditions. The agent must infer the workflow ordering from the parameter description in the schema rather than from the description itself.

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