Memory status

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

With no annotations, the description carries the full transparency burden, and it does well: it discloses that the tool reads the store directly, requires no network or embedding, and notes the selfFacets-is-always-0 quirk with its root cause (no consolidation pass). This adds meaningful behavioral information an agent would not infer from the name or empty schema.

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 this concise and well-structured: the main sentence states the function, the second sentence adds differentiating behavior (no embedding/network), the third gives usage guidance, and the parenthetical discloses a critical invariant. No word is wasted, and the most important information is 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?

For a read-only, zero-parameter tool with no output schema, the description is fully sufficient: it explains what the tool returns, when to call it, what side effects it does not have, and the only significant edge case. The agent has everything needed to invoke it correctly.

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 tool accepts zero parameters, so the description does not need to explain parameter behavior. It instead clarifies what the output contains (counts and recent facts), which is the appropriate compensating information. The baseline of 4 for zero-parameter tools applies.

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 states a specific verb ('Summarize') and a precise resource ('what is currently in memory'), with output detail ('counts plus the most recently stored facts'). It also distinguishes itself from search-like siblings by noting it reads the store directly without embedding calls or network access, so an agent can tell this from memory_search at a glance.

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 gives explicit usage context: 'Use to orient yourself at session start, or when the user asks what you remember.' This is clear and actionable. However, it does not explicitly state when to prefer a sibling alternative such as memory_search for a specific fact lookup, so it stops one step short of full exclusion guidance.

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