Watch channel

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

Beyond the annotations, it discloses meaningful behavior: private/presence channels are signed automatically, the watcher joins as a visible presence member, and long watches emit progress every few seconds. These are non-obvious side effects an agent needs, and they do not contradict readOnlyHint/openWorldHint.

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?

Four sentences, front-loaded with what the tool does and followed by usage, side effects, and progress behavior. Every sentence carries distinct information with no redundancy.

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 adequately conveys the lifecycle and the presence/signing side effects, plus progress reporting. It could say more about what the collected events look like on return, but the essentials for correct invocation are present.

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 baseline is 3, but the description adds real meaning beyond the schema: channel_data is characterized as presence member data ('the watcher joins as a member') and the drop-versus-count behavior of max_events is reinforced. It stops short of documenting until_events semantics.

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 opens with a precise verb+resource: subscribe to a channel over WebSocket, collect events, then disconnect. It is clearly distinguished from siblings like publish_event and list_channels, and even frames the publish/watch pairing explicitly.

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?

It gives concrete when-to-use cases (confirm events are flowing, inspect payload shapes, test a publish end to end) including the ordering hint 'start the watch, then publish'. It does not state when NOT to use it or name sibling alternatives for those cases, so it falls short of a 5.

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