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

Annotations only declare a safe read (readOnlyHint=true), so the description carries the rest of the burden and does so: it discloses the default exclusion of completed agents, the nuance that `trigger_count` counts only triggers that can still fire, and a practical caveat that `result['agents']` is a dict, not directly iterable. This is meaningful behavior beyond annotations, though it stops short of pagination or ordering details.

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 summary sentence is front-loaded and efficient, and the tagged structure aids scanning. There is mild redundancy: the pointer to `get_agent_details` for goal/workspace/trigger bodies appears in both the summary and the returns block.

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 correctly assumes responsibility for describing the return value, enumerating every summary field and noting the access pattern via `result['agents']`. For a one-parameter read tool with readOnlyHint, nothing an agent needs to call it correctly is missing.

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 100% and the single `include_completed` parameter is already documented there. The description's 'By default excludes completed agents' corroborates the default but adds no syntax or format detail beyond the schema, so the 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 (List) and resource (the user's agents) plus the shape of the result ('one-line summaries: status, run counts, and a trigger count'). It also names the distinguishing sibling, `get_agent_details`, so an agent can tell the two apart without opening either schema.

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 states the default filtering behavior ('By default excludes completed agents') and routes the agent to the alternative: use `get_agent_details(agent_id)` when goal, workspace, or full trigger bodies are needed. When-to-use and the alternative are both spelled out.

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