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

Beyond annotations, which only mark the tool as idempotent, non-read-only, and non-destructive, the description explains the two-phase approval flow: nothing is created until the owner approves it in the Widely app. It describes the charging model, optional Plus membership and phone number priced now but charged on the new account after approval, the rule that card details are not accepted, and the approval prerequisite that 'give access' must stay ticked. These are non-obvious runtime behaviors that annotations cannot convey.

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?

The key constraint, that nothing is created until the owner approves, is front-loaded in the second sentence, and each sentence carries a distinct fact. Some sentences are dense, and the final connection-setup passage reads as a run-on of procedural steps; however, very little is redundant.

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 14-parameter mutation with no output schema, the description covers the essentials: approval gating, charging timing, idempotency, preview mode, and account-discovery recovery steps. The main remaining gap is that the numeric and telephony parameters are left opaque, but an agent could make a reasonable call from what is provided.

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?

With 14 parameters and only 50% schema description coverage, the description adds meaning for confirm (preview vs. submit), idempotency_key (replays instead of charging again), plan_tier (Plus membership after approval), and country (optional phone number). However, it leaves sku_id, number_sids, number_type, did_group_id, stock_did_id, channel_count, and includes_origin_calls entirely unexplained in both the schema and the description. This is adequate but clearly incomplete for a parameter set this size.

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 definition uses a specific verb and resource: 'Prepares another business account owned by the signed-in user.' This clearly distinguishes it from read tools like get_account. The one weakness is that the purpose does not name a direct alternative such as open_platform_account; instead, differentiation comes from inference. Overall it is still clear and agent-usable.

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 gives concrete when-to-use guidance: omit confirm for a preview, use the same idempotency_key to avoid duplicate charges, and call get_account without an account argument to list connection accounts. It also explains what to do when the account is not on the connection: add it from Connected apps, or reconnect and tick it. It does not explicitly weigh this tool against sibling creation tools, so it stops short of a 5.

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