save_skill

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

With no annotations, the description carries the full burden. It discloses that the file is persistent and private, and that saving an existing name performs a partial update. This gives agents an accurate mental model, though it stops short of detailing error conditions or side effects.

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 structured with the purpose first, followed by usage examples and parameter guidance. Every sentence contributes to understanding without redundancy.

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 low complexity, the description covers the intended use, parameter roles, and update semantics comprehensively. The sibling context reinforces the need for clarity, which this description satisfies.

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 is 0%, but the description explains each parameter: 'name' (short, unique), 'rule' (the rule itself), 'category' (grouping), and 'notes'. It also clarifies the optional nature and the update behavior, providing essential meaning beyond the bare 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?

The description clearly states the action ('Save or update a rule/skill') and the resource ('persistent, private skills file'), distinguishing it from sibling tools like list_skills, get_skill, and delete_skill. The update semantics are also specified, making the scope unambiguous.

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 provides explicit usage context: 'Use this for durable lessons and rules you want to follow in future sessions' and gives concrete examples. It doesn't explicitly mention alternatives or exclusions, but the context is clear enough to differentiate from similar tools like save_strategy.

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