fable_remember

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

No annotations provided, so description carries full burden. Discloses durability and auto-injection at session start, but does not mention overwrite behavior or limits. Adequate for a simple tool.

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?

Two sentences: first states core function, second gives usage guidance. No fluff, front-loaded, every sentence 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?

No output schema, no annotations. Description covers persistence and injection but lacks details on limits (e.g., character cap), overwrite behavior, or return value. Adequate for simple tool but has gaps.

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 50%: 'project' has a description in schema, 'fact' does not. Tool description implies 'fact' is the fact to remember but adds no extra detail. Description provides marginal value over schema.

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 clearly states verb 'store', resource 'durable fact', and scope 'across all future sessions with auto-injection'. Distinguishes itself from siblings by emphasizing persistence and injection behavior.

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 'Use when the user says "remember that..." or states a lasting preference/decision.' Provides clear usage context but lacks explicit when-not-to-use or alternatives, though siblings like fable_context are implied.

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