get_session_info

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

No annotations exist, so the description bears the full burden. It implies a read-only operation via 'Retrieve' and adds a useful behavior note: 'uses most recent if not provided.' However, it does not explain error behavior, what happens if no session exists, or what 'session state information' specifically includes, leaving gaps for a simple getter.

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 remarkably concise: a one-line purpose statement followed by a clear Args/Returns structure. Every sentence earns its place, and the most important information is front-loaded. There is zero redundancy or fluff.

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 the tool's simplicity (one optional parameter, output schema present), the description covers the essential aspects: what it does, the parameter's behavior, and a return summary. It omits potential error states and when to use it, but the output schema likely handles return structure, so the description is adequate for a getter.

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 does by explaining session_id's purpose ('Session identifier') and its optionality with the default behavior ('uses most recent if not provided'). This adds meaning beyond the raw schema, though it could go further with format constraints or edge cases.

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 the tool's purpose with a specific verb and resource: 'Retrieve information about the current session state.' It is distinguishable from siblings like query_can_messages or get_statistics, though it does not explicitly differentiate itself, which would warrant a 5. The mention of 'session state' makes the purpose clear without ambiguity.

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 no guidance on when to use this tool versus alternatives. It does not mention any prerequisites, context, or scenarios where this tool is preferred over siblings like get_statistics or find_errors. The only implicit hint is the name, but that is insufficient.

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