session_card

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

With no annotations provided, the description must carry the behavioral burden. It discloses output format (text + PNG pages), theme behaviors (transparent background for clear), unit behavior (each set keeps its logged unit), and style differences (full spans pages, story is one screen). It does not state whether the operation is read-only, how errors are handled, or what happens if no session exists, leaving some gaps.

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 a single dense sentence that packs purpose and parameter details efficiently. It front-loads the purpose and then explains options. It could benefit from line breaks for readability, but it is concise with no wasted words.

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 tool with 4 parameters and no output schema, the description covers the output format, selection logic, and three parameters. It omits session_id semantics and does not address edge cases like missing sessions or error behavior. This leaves an agent without full guidance for correct invocation, especially when specifying a session.

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%, so the description must explain parameters. It describes theme, unit, and style with their allowed values and meanings, but does not explain session_id at all. Since session_id is a key parameter (though optional), the description is incomplete for one of four parameters.

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 states a clear purpose: generates a summary card for a workout, selecting the open session or latest if none. It names the resource (workout) and specifies the output format (text + PNG pages). It does not explicitly differentiate from sibling tools, but the context of 'workout' distinguishes it from food-related siblings.

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 context about when to use the tool (for a workout) and how the session is selected, but does not explicitly state when to prefer this over other tools. There is no mention of alternatives or exclusions, so usage guidance is implied rather than explicit.

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