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

With no annotations, the description carries the full burden of disclosing behavior. It states the response is the decrypted payload value, clarifies the meaning of 404, and indicates the authentication mechanism (Bearer token). It does not mention potential rate limits, other error codes, or whether the operation has side effects, but as a simple GET, these are less critical.

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 succinct and well-structured: a clear one-sentence purpose, an important error-handling note, and then concise technical details (HTTP method, authentication, config preference). Every sentence adds value without 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?

Given there is no output schema, the description sufficiently explains what the tool returns (the decrypted value) and covers a key error case (404). It does not specify the exact response format (e.g., JSON structure, content type), but for a simple value retrieval this may be acceptable. The description is complete enough for an agent to understand the tool's core usage.

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?

The input schema already provides descriptions for all parameters (key, host, appId, workspaceName, sessionToken), so the baseline is high. The description adds extra context for sessionToken by specifying it is forwarded as a Bearer token, and for workspaceName/appId by recommending them as stable config. It does not add meaning for key or host, but the schema descriptions are already clear.

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 verb ('Retrieves') and clearly identifies the resource (a single value from the session payload for a given key). It distinguishes itself from sibling tools like get_sessions (list) and get_sessions_identity (identity data) by focusing on a single key/value lookup.

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 provides practical usage guidance: it explicitly explains the 404 handling as a normal first-use case, mentions the requirement for auth.sessionToken to be forwarded as a Bearer token, and advises preferring connection.workspaceName and appId over dynamically generated identity fields. However, it does not explicitly compare to alternative tools (e.g., when to use this over get_sessions) or mention any preconditions beyond the token.

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