init_session

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

Annotations already indicate readOnlyHint=true and idempotentHint=true. The description adds helpful behavioral context: it returns tasks in progress within a 3-day window. No contradictions with annotations.

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 concise with a clear purpose sentence followed by structured Args and Returns sections. It could be slightly more concise by not repeating schema descriptions, but overall it is well-organized and front-loaded.

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 presence of an output schema (mentioned in the description), the tool definition is complete: it explains purpose, parameters, and return structure. The annotations provide safety information. No gaps remain for an initialization 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?

The description repeats the parameter names and descriptions from the input schema (exact match filtering). Since the schema already provides full descriptions for both parameters, the description adds no new meaning beyond what is in the schema, meriting a baseline score of 3.

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 initializes a session and returns a list of recent tasks in progress within the last 3 days to restore context. The verb 'returns' and resource 'tasks in progress' are specific, and the purpose is well distinguished from siblings like list_recent_sessions.

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 explicitly says 'Called when the session starts', providing clear context for when to use the tool. However, it does not discuss when not to use it or mention alternative tools for similar purposes.

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