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

With no annotations, the description carries the behavioral disclosure burden. It reveals an important side effect: if distill defaults to true, the transcript is queued for a background worker to create durable org-scoped memories. It does not cover session finality, reversibility, or failure behavior, but the key side effect is transparently disclosed.

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 two sentences with no filler: the first states the core action, the second explains the optional distill behavior. It is front-loaded and every clause earns its place.

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 low-complexity tool with full schema coverage and an output schema, this description is complete. It covers the required input, the optional flag, and the important side effect, so an agent can invoke the tool correctly without needing additional context.

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 coverage is 100%, so the baseline is 3. The description adds meaningful detail for the distill parameter, explaining the background worker and durable org-scoped memory outcome beyond the schema's 'semantic/episodic memory' phrasing, and it clarifies the default behavior. session_id is adequately documented by the schema itself.

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 first sentence states a specific action and object: 'Close a working-memory session.' This clearly identifies what the tool does and contrasts with sibling tools like memory_session_open and memory_session_append through the verb 'Close'.

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 does not explicitly say when to use this tool versus alternatives such as memory_session_open or memory_session_append. The only conditional guidance is about the distill flag, not about choosing this tool, so usage is implied rather than stated.

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