record_preference

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

Annotations indicate a non-read-only, non-destructive operation, which aligns with the description 'Append' and 'durable'. The description adds context about the target (preferences file) and the nature of data (one-line rules), but doesn't elaborate on file creation or duplicate handling. Still, it sufficiently discloses behavior beyond annotations.

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 front-loaded with purpose, then usage guidelines, then negative guidance. Every sentence adds essential information with no redundancy or filler.

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?

Given the tool's simplicity (2 params, no output schema, no enums), the description fully covers purpose, when to use, and parameter semantics. No gaps remain for correct invocation.

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 has 100% coverage with descriptions for both `observation` and `category`. The description reinforces the expected format with examples ('One-line rule...', 'Optional category tag... Examples: filing, naming...') and provides a concrete example for observation, clarifying usage beyond the schema alone.

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 clearly states the action: 'Append a durable user preference, convention, or correction to the vault's preferences file.' It also gives specific examples of when to use (user corrects a proposal on filing path, naming pattern, etc.), distinguishing it from one-off feedback.

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?

Explicitly says 'Call this when the user corrects a proposal...' and provides a clear negative: 'Do NOT record one-off disagreements or transient feedback.' This helps the agent decide when to invoke this tool vs. alternative feedback mechanisms.

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