upsert_account_balance_history

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

Beyond the idempotentHint annotation, the description discloses important behavior: the current month cannot be written, the request is atomic/all-or-nothing, and the response contains only submitted entries rather than full history. This is substantial behavioral context that annotations alone would not provide.

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 filler. The core action is front-loaded, followed by the most important constraints, atomicity, and response behavior. Every sentence earns its place.

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?

The description covers the critical behavioral aspects needed to call the tool safely: past-month restriction, atomicity, and response contents. The rich schema handles parameter details, and the sibling list plus account_type description clarify scope. It does not spell out the synced-crypto exclusion, but that is adequately handled elsewhere.

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%, so the schema already documents every parameter thoroughly. The description reinforces the all-or-nothing behavior of the balances array and the past-month rule, but adds no per-parameter meaning beyond what the schema provides. Baseline 3 is appropriate.

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 states a clear verb and resource: 'Create or update monthly balance history entries for a single account.' It is specific and not a tautology, though it does not explicitly distinguish itself from the close sibling upsert_crypto_synced_balance_history; that distinction is left to the schema and sibling names.

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 gives useful constraints such as past-month-only and all-or-nothing semantics, but it does not explicitly say when to use this tool versus alternatives like upsert_crypto_synced_balance_history or get_account_balance_history. Usage context is implied rather than stated with exclusions.

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