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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered and the bracketed '[read-only]' is redundant. The description still adds real context: the data source (OAuth sign-in vs API key), the meaning of a null brand (account-wide), and the wrapped endpoint GET /api/v2/ping.

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 sentences plus an endpoint note, with the return shape front-loaded after a single leading verb. Nothing is padded and the ordering instruction closes it cleanly.

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 enumerates the returned fields and explains the null-vs-populated brand distinction, which is exactly the gap an output schema would otherwise fill. An agent has everything needed to call it and interpret the result.

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?

Zero parameters, so the schema baseline of 4 applies and the description has nothing it could clarify. It correctly implies a single global call with no scoping arguments.

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 names a concrete resource and verb: it returns the identity the connection belongs to, enumerating userId, plan tier, and brandId/brandName. That is distinguishable from every sibling in the list, none of which report connection identity.

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?

'Call this first to learn what the connection can reach' gives explicit ordering guidance an agent can act on. It stops short of saying when not to call it or naming an alternative, but with zero required inputs and no sibling overlap the omission is minor.

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