start_session

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

With no annotations provided, the description carries full burden and does well by disclosing key behavioral traits: it costs 1 credit, automatically records time, returns an ak_id needed for future operations, and has default values for all parameters. It doesn't mention error conditions or rate limits.

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?

Perfectly structured with purpose statement first, cost disclosure second, behavioral details third, and parameter explanations in a clear Args section. Every sentence earns its place with 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 creation tool with no annotations and no output schema, the description is quite complete - covering purpose, cost, behavior, and all parameters. It could mention what happens if the session fails to start or provide more detail about the return format beyond 'including its ak_id'.

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?

With 0% schema description coverage, the description fully compensates by explaining all three parameters: activity_id (with default and reference to list_activities), timezone (with format example and default), and intended_sec (with meaning of default value). This adds substantial meaning beyond the bare schema.

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 verb 'Start' and resource 'new behavioral session', distinguishing it from sibling tools like 'stop_session' or 'check_session'. It specifies this creates a new session with a unique identifier (ak_id) needed for later operations.

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 clear context about when to use this tool (to begin a session) and references 'list_activities' for activity options, but doesn't explicitly state when NOT to use it or compare it directly to alternatives like 'create_activity'.

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