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

No annotations or output schema are present, so the description must disclose side effects and state changes on its own. It only says 'extend,' without mentioning that it modifies the current experience, whether the change is reversible, what happens at the duration_max limit, or what response the agent should expect.

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 one active sentence with no filler, so it is structurally concise and front-loaded. It is somewhat too terse, but that is a completeness issue rather than a conciseness issue.

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 four parameters, an unannotated mutation, and no output schema, the description is incomplete. It provides only a minimal purpose statement, omitting how parameters drive the behavior, failure modes, and how the tool relates to the rest of the hit/come_down lifecycle.

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 0%, and the description adds no parameter information. None of mode, flavor, intensity, or duration_minutes is mentioned, leaving the enum values and numeric ranges unexplained.

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 identifies a verb ('extend') and a target ('current Synapse Lounge experience'), so it is not a tautology. However, 'experience' is vague and does not explain whether this extends a hit, session duration, or mode; it depends on the tool name and sibling tools for context.

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 word 'current' is an implied usage constraint, signaling that an active experience must exist before calling this tool. It gives no explicit guidance about choosing this over take_hit for a new experience or come_down for ending one, and no behavior is described for the no-current-experience case.

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