save_session

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

No annotations are provided, so the description carries full burden. It discloses key update behavior ('Keys are updated in place if they already exist') and mentions multiple keys per session, but lacks details on persistence guarantees, auth requirements, or potential 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 two sentences long, front-loaded with the action, and every word earns its place. It efficiently conveys purpose, usage, and key behavior 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?

For a simple three-parameter tool with no output schema and no annotations, the description is fairly complete. It explains the key-value nature, session creation, and typical use cases. Minor omissions (e.g., return value, limits) prevent a perfect score.

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?

The input schema already documents all three parameters (100% coverage). The description adds value by providing examples for session name and value, clarifying that sessions are created if they don't exist, and that values can be various content types. This exceeds baseline 3.

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 tool's purpose: 'Save a key-value entry to a named session.' It specifies the action (save), the resource (key-value entry in a session), and provides examples of usage (persist decisions, context, plans). This distinguishes it from sibling tools like load_session, delete_session, etc.

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 advises to use it 'to persist decisions, context, plans, and findings between coding sessions,' which provides clear context. However, it does not explicitly mention when not to use it or compare it directly to alternatives like save_learning, leaving some ambiguity.

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