Start a study session

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

Annotations indicate this is not read-only, not idempotent, and not destructive, but they don't explain behavior. The description adds valuable context by mentioning the return of a sessionId and shuffled cards, and the expectation of finishing with submit_review. This goes beyond the annotations, providing a clear workflow.

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, front-loaded with the primary action, and contains no fluff. Every sentence earns its place: the first states the purpose, the second covers the return value and next step.

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 output schema exists, the description doesn't need to detail return values. It covers the purpose, return, and workflow, and the schema covers parameters. The SM-2 reference adds context about the scheduling system, making the tool's role clear within the broader study session flow.

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 100%, so the baseline is 3. The description does not add extra parameter details beyond what the schema already explains, but it doesn't need to since all parameters are fully described with enums and defaults.

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: 'Start a spaced-repetition study session for a set.' It specifies the resource (a set) and distinguishes itself from siblings like generate_cards (which creates cards) and submit_review (which records results) by describing the session-starting behavior and the return of sessionId and shuffled cards.

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 gives clear workflow context by stating 'Finish with submit_review to record results,' but it does not explicitly call out alternatives or exclusions. It implies when to use (when starting a study session) without directly comparing to sibling tools, so it falls short of a 5.

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