Store a durable preference

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

Annotations indicate this is a write operation and not read-only. The description adds valuable behavioral context beyond annotations: restating reinforces rather than duplicating, and contradictory corrections/constraints retire softer memories. This discloses conflict-resolution behavior that the schema and annotations do not.

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?

Three sentences with no filler; each sentence earns its place: primary action/purpose, dedup/retirement behavior, and usage boundary. There is no redundant repetition of schema or annotation information.

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 six-parameter write tool with no output schema, the description plus well-documented schema provides enough context to invoke correctly. It covers purpose, durability semantics, conflict handling, and when not to use it. A short example could push it to a 5, but nothing essential 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 high at 83%, so the baseline is 3. The description slightly reinforces parameter concepts ('preference', 'constraint', 'correction') but adds no new meaning beyond the schema's own parameter documentation.

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?

Description uses a specific verb ('Record') and names the resource ('a preference, rule, or correction') with an explicit purpose ('so future briefings honour it'). It clearly distinguishes the tool from sibling read/delete tools like recall and forget by emphasizing durable preference storage.

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 states when to use it: 'Use for standing rules, never for one-off task instructions.' It provides a clear exclusion, though it does not explicitly name alternative tools for the excluded cases; the sibling set makes those alternatives inferable.

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