Window: list spaces

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

No annotations exist, so the description bears the full disclosure burden. Listing spaces/tabs/terminals strongly implies a read-only, non-destructive operation, and the 'inspect before acting' note adds useful workflow context, but nothing states permissions, side effects, or cost.

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?

Two short sentences, with the return content front-loaded and the usage advice second. Nothing is wasted or buried.

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?

With no output schema, the description must describe the return value, and it does: spaces, tabs, terminals, and pane IDs. It does not explain the shape of the response (nesting, field names) or whether it reflects a snapshot, leaving a minor gap.

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 schema-side to compensate for; the baseline for a parameterless tool is 4. The description correctly adds no parameter discussion, which is appropriate.

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 names the resource precisely — spaces, their tabs and terminals, including pane IDs, in the open Herdr window — which maps cleanly onto the 'list' verb implied by the name. It does not explicitly distinguish itself from nearby siblings like herdr_list or herdr_app_status, so it stops short of a 5.

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?

'Inspect before acting; use these IDs rather than guessing' gives a clear usage context and even a workflow recommendation. It does not name an alternative tool or state when-not to use it, so it lacks the explicit exclusions that would earn a 5.

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