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

Annotations cover the safety profile (readOnlyHint=true) allowing the lower bar, but the description still adds real behavioural context: the two connect_mode semantics and that it returns where the merchant generates the credential. It does not discuss pagination or result size, which keeps it from a 5.

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 dense sentences that front-load the resource before the connect_mode rules, and every clause earns its place. The stray '[#21af2f]' artifact at the end is noise that costs a point.

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 carries the burden of describing returns and does so for the two fields that matter (connect_mode and credential origin). Nothing essential for calling or interpreting it is missing, though a note on ordering or scope of the provider list would round it out.

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% and the single workspace parameter is fully documented in the schema, including the multi-workspace failure mode. The description adds nothing about parameters, 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?

States a specific resource — the fulfillment providers and sales channels this account may connect — and goes further by defining the connect_mode field values it returns. An agent can distinguish this from list_catalog_providers, connect_fulfillment_provider, or connect_sales_channel without opening any 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?

Explicitly prescribes when to call it ('Use this before asking a user for anything, so you ask for the right thing') and routes the agent onward: in_chat mode is handled in-conversation by requesting a credential, browser mode requires start_channel_connect plus polling. That is a complete decision path, not just context.

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