brief

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

No annotations are supplied, so the description carries the full behavioral burden. It does imply the operation is a small, passively injected, read-only payload ('注入的那一小段'), but it never states that it is non-mutating, gives no return shape or ordering, and does not say whether omitted memories can be retrieved elsewhere.

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?

A single compact sentence with no padding, and the key scoping idea (small, injected at wake-up) is front-loaded. It is arguably too terse for the informational load rather than verbose.

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?

With no annotations and no output schema, the description is the only place an agent could learn what the call actually yields – yet it says only 'a few memories'. Nothing about which fields come back, how they are ordered, or whether the set is stable across calls, which is critical since producing that payload is the tool's entire purpose.

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% – both 'limit' (default 8) and 'scope' are already documented in the schema. The description only gestures at these via '几条' (a few) and does not add format or semantic nuance, so baseline 3 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 communicates the resource – a small curated set of the most important memories about the user, delivered at wake-up – which does distinguish it from the search-like sibling 'recall'. But it uses a noun phrase with no clear verb ('brief' is not stated to 'return' or 'fetch' anything), and the metaphor '最硬的记忆' (hardest memories) leaves the selection criteria undefined.

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?

'唤醒时' (at wake-up) implies the trigger condition, which is genuinely useful usage context. However, no alternative is named and no exclusion is given: with 'recall' and 'remember' as siblings, the agent must infer that 'brief' is the cheap session-start fetch rather than a targeted lookup.

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