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

With no annotations, the description carries the burden well: it discloses the returned sessionToken, its 7-day validity, the need to treat it as a secret, and its downstream use. It does not describe error behavior for invalid signatures, but the core behavioral traits are 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?

Two sentences, front-loaded with the step number and dependency, then the return value and security note. No wasted words.

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 three-parameter authentication tool with no annotations or output schema, the description covers the prerequisite, inputs, return value, lifetime, and security handling. The only gap is the unmentioned walletAddress parameter and lack of error-case detail.

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 0%, so the description must compensate. It clarifies that message comes from prepare_login and that signature corresponds to it, but it never mentions the required walletAddress parameter, leaving one of three parameters without added meaning.

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 precise role: step 2 of signing in, sending the prepared message and signature to obtain a sessionToken. It distinguishes itself from the sibling prepare_login by explicitly naming the preceding step and the returned credential.

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?

It clearly says to use the message from prepare_login and its signature, and that the resulting sessionToken must be passed to tools needing a signed-in wallet. This gives strong when-to-use context, though it does not explicitly state exclusions or failure conditions.

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