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

readOnlyHint=true already establishes this is a safe read. The description adds useful return-content context (sender, limits, consumption) and identifies the underlying GET endpoint, but discloses nothing about pagination behavior, result volume, or ordering beyond what the schema's page/page_size fields imply.

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 tight sentences, front-loaded with purpose and return content, followed by a short endpoint citation. Little waste, though the endpoint reference adds marginal value for an agent choosing a 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?

No output schema exists, yet the description names the returned fields (default sender, daily and monthly limits, consumption) and the schema itself covers paging via page/page_size and next_page. For a read-only list tool with zero required parameters, an agent has enough to call it correctly.

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%, so every parameter (including the flow and type enums) is already documented in the schema. The description restates the flow and type values without adding filtering semantics, format, or interaction rules, so it matches the baseline for a fully-covered schema.

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 and resource ('List messaging channels') plus the type and flow dimensions and the fields returned (default sender, daily/monthly limits, consumption), so an agent knows exactly what it gets back. It does not, however, differentiate itself from siblings such as get_channel or list_consumptions, whose content overlaps with the consumption data mentioned here.

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?

The line 'A channel id is needed to scope messages or consumption to one channel' implies the practical reason to call this tool (obtaining a channel id), but it never explicitly says when to use this versus get_channel or list_consumptions, and gives no exclusions or prerequisites.

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