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

The readOnlyHint annotation already signals this is a safe read operation. The description adds useful context about which metrics are returned (connections, publishers, subscribers, presence members) and gives the REST endpoint, but does not disclose auth requirements, rate limits, time-window semantics, or response shape.

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 tightly written sentences: the first gives purpose and scope, the second gives the REST endpoint. Nothing is wasted and the core purpose is front-loaded.

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 simple read-only, one-parameter tool with full schema coverage and a readOnlyHint annotation, the description is nearly complete. It names the returned metrics, which is helpful without an output schema, but it could go slightly further to clarify whether 'presence members' means counts or detailed presence data.

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% for the single 'channel' parameter, and the schema already describes it as 'Channel name.' The description reinforces that the channel is a single named channel but adds no syntax or format detail beyond the schema, so the baseline of 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 ('Get') and resource ('status and occupancy metrics for a single channel'), and lists the metrics included. The word 'single' implicitly distinguishes it from list-oriented siblings like ably_list_channels, but it does not explicitly differentiate from similarly scoped siblings such as ably_get_presence or ably_get_channel_history.

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: call this when you have a specific channel and need its status/occupancy. There are no explicit when-to-use, when-not-to-use, or alternative-tool instructions, so an agent must infer selection from the tool name and description alone.

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