List all registered Homes.com sessions

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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, closed-world), so the bar is lower, and the description adds genuinely non-obvious behavior: the empty/null degenerate case and the crucial warning that the registry has no effect on which Homes.com account requests actually hit. That prevents a real misinterpretation, though it is silent on ordering or the bridge-connected precondition for calls succeeding.

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?

Three sentences, front-loaded with what is returned, then the empty-state behavior, then the label-only caveat. Each sentence earns its place, though the bridge-extension sentence is contextual padding rather than core to invoking this tool.

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?

There is no output schema, so the description carries the return-value burden and does so adequately: it names the returned fields, their degenerate values, and the caveat about their meaning. Anything missing is minor for a zero-arg local registry read.

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 tool takes zero parameters, so there is nothing to disambiguate; baseline 4 applies. The description spends no words restating an empty schema, which is correct.

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 (list) and resource (registered account labels + active_session_id), and goes further by clarifying the registry is label-only and does not control which account requests use. That semantic distinction cleanly separates it from homes_register_session and homes_set_active_session, which an agent might otherwise confuse it with.

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?

Usage is implied rather than stated: an agent can infer this is a read of the local session registry, and the closing sentence points to the real mechanism for switching accounts (sign the bridge tab in). However, no sibling tool is named and there is no explicit 'use this when / not when' routing.

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