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

Annotations already provide readOnlyHint and destructive hints, and the description adds useful behavior boundaries: it never signs or opens the session. It also supplies non-obvious context about the session being 30-day and game-only. No annotation contradiction is present.

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?

The description is only two short sentences with no filler. The key action, session constraints, and non-signing behavior are all positioned clearly and economically.

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 two-parameter, read-only tool with full schema coverage and an output schema, the description provides the essential context. The main missing detail, an explicit pointer to the companion tool that finally signs or opens the session, is not strictly required for selecting or invoking this tool.

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 owner and tokenId are already documented in the input schema. The description does not add meaningful parameter-level meaning beyond mentioning that the output is owner-readable text. This is a standard baseline score for full schema coverage.

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 clearly states a specific verb and resource: prepare owner-readable text for a 30-day, game-only session. It also clarifies what the tool does not do, namely sign or open the session. It lacks explicit sibling differentiation, but the action itself is unambiguous.

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 description implies this tool is only for the preparation phase and should not be used when signing or opening the session is desired. However, it does not name an alternative tool or provide explicit when-to-use guidance relative to the many sibling prepare_* tools.

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