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

Annotations already mark the tool as read-only and idempotent, and the description adds valuable context: the {results, errors} batch shape, the provider_incident block, and a warning about unreliable credit limits/balances during an open provider incident, with explicit instruction not to present those values as real. This goes beyond annotations and significantly helps the agent handle edge cases.

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 description is structured with the main purpose first, then usage, then batch shape, then the incident caveat. Every sentence adds value, but the last sentence on provider_incident is a bit long with a potentially confusing example ('limit near 1,00'). It's still concise overall.

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 tool with one parameter and no output schema, the description covers the return shape, batch behavior, and important data reliability caveats. It provides enough for the agent to use the tool correctly and interpret results safely, leaving no major gaps.

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 has no descriptions (0% coverage), but the description directly explains the only parameter: account_ids is an array, accepts 1–50 items, and is used per id. It also clarifies the batch result shape. This compensates well for the missing schema descriptions, though it doesn't go into exhaustive detail about array item formatting or edge cases.

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 clearly states it returns full account objects including extended creditData, which is specific and differentiates from simpler listing/balance tools. It references the endpoint and scopes by id, but doesn't explicitly name sibling tools to distinguish, so it falls short of a 5.

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 description indicates how to pass account_ids (array of 1-50) and mentions batch behavior, implying use for detailed account retrieval. However, it doesn't explicitly state when to use this tool versus alternatives like openfinance_get_account_balance or openfinance_list_accounts, nor does it exclude any use cases.

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