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

The description adds a key behavioral trait beyond the readOnlyHint annotation: this returns the global catalog of what COULD be connected, not the workspace's configured providers, which prevents a common category error when comparing against list_providers. It doesn't address response size or pagination, but the scope disclosure is the more important behavioral fact and the safety profile is already covered by the annotation.

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?

Three sentences with no fluff, front-loaded with the core operation, then the sibling differentiation, then user-question framing. The restatement of purpose in question form is mildly redundant but earns its place by helping agents map natural-language intent to the 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?

For a read-only, zero-required-param listing tool with full schema coverage, the description covers selection semantics, scope, and setup relevance. It doesn't describe the response shape, but the tool's low complexity and clear schema/annotations make the description complete enough for correct invocation.

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% — all three params (keys, name, channel) have descriptions. The description reinforces that each catalog entry includes configuration expectations, but adds no parameter-level 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?

The description uses a specific verb+resource ('List the provider integrations Courier supports and the configuration each one expects') and immediately differentiates from the sibling list_providers by clarifying catalog vs workspace config. It also frames the tool by the two questions it answers, so an agent can match it to user intent without opening the 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?

It explicitly says when not to use it — 'use list_providers for that' — drawing the workspace-config vs catalog boundary. The phrasing 'what do I need in order to set up this provider' implies the setup/onboarding context that would trigger selection.

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