Get session context

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

Annotations cover read-only, non-destructive, closed-world, and idempotent behavior. The description adds valuable context not in annotations: the digest reflects recent activity, so two calls minutes apart may differ. This addresses data freshness, which annotations cannot convey. The only minor gap is that it doesn't detail return format or rate limits, but for a read-only tool this is largely sufficient.

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 four sentences with zero waste, front-loading the core purpose and timing before alternatives and behavioral nuance. Every sentence contributes directly to correct selection and invocation.

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 read-only tool with no output schema, the description is complete: it states the purpose, when to call it, alternatives, and a behavioral trait not captured by annotations. The parameter is schema-documented, and the annotations cover safety. Nothing essential for an agent to call it correctly is missing.

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 100% for the single 'limit' parameter, which is fully documented in the schema. The description does not add meaning beyond what the schema provides, so baseline 3 is appropriate.

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 uses a specific verb ('Pull a short digest') and resource ('recent memory from the human's active threads and open tasks'), and explicitly distinguishes itself from siblings like recall and manage. An agent can immediately understand what this tool does and when it differs from alternatives.

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 explicitly states when to call ('once at session start') and when not to ('For answering a specific question, use recall instead', 'For entries still awaiting approval, use manage with action list_pending'). The alternatives are named with the conditions that select them, leaving nothing to inference.

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