Switch which registered OneHome session is active

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

Annotations already cover safety/idempotency (readOnly false, idempotent, non-destructive). The description adds the routing semantics that no structured field carries: which requests the active session answers and the error case when a ~MLS id matches multiple sessions. It stops short of saying whether the switch persists across calls or what it returns.

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?

Front-loaded with the action, then rationale, then sourcing, then routing rules. Dense but each sentence earns its place; the long final sentence is a bit packed but justifies its length by explaining routing precedence and the ambiguity error.

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 single-parameter switching tool with no output schema, the description covers when to use, input sourcing, and routing consequences. It leaves minor gaps (persistence and return value) but is otherwise complete enough to call correctly.

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 100%, so the session_id parameter is already documented. The description reinforces the two legitimate sources (set_auth response, get_session_context), but adds no format or syntax detail beyond the schema. Baseline 3 applies.

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?

States a specific verb (Force/set active) and resource (registered session), and precisely distinguishes from siblings: it is the tool that overrides MLS-suffix routing, while set_auth registers and get_session_context lists.

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?

Explicitly gives the trigger condition (MLS-suffix routing picks the wrong session) with three concrete examples, and states where the session_id comes from. The agent knows exactly when to reach for this over other session tools.

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