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

With annotations declaring a non-idempotent, non-destructive write, the description adds real behavioral context beyond them: non-USD currency is rejected pre-launch, institution_login_url is https-only and normalizes bare domains, empty string removes the link, and include_in_debt_paydown explicitly does NOT affect net worth/total debt/balance sheet. The 'use with caution' on balance is vague, and idempotency behavior isn't addressed, keeping 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?

Purpose is front-loaded in the first sentence, and the parameter block is dense but every line adds needed meaning given 0% schema coverage. The Python 'Args:'/'Returns:' docstring framing and an internal file reference (docs/CURRENCY_RESTORE_TODO.md) are minor formatting leaks rather than wasted content.

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 26-parameter mutation with no output schema and minimal annotation detail, the description covers every input precisely and states the return ('Updated account details'). The only thinness is the terse return statement and lack of any error/permission behavior, but the input surface is complete.

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 0%, so the description carries the entire burden — and it documents all 26 parameters with meaning beyond names: enum values for account_type, YYYY-MM-DD formats for loan dates, 'mortgage only' scoping for escrow fields, HELOC/ARM scoping for second-term fields, and behavioral semantics for the threshold/alert parameters (override vs global default, clear vs set). This is exactly the compensation the low coverage requires.

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 clear verb+resource: 'Update an existing financial account.' An agent immediately knows this mutates an account record. However, it does not distinguish itself from close siblings like override_account_balance, create_account, or update_account's relationship to them, so an agent must infer routing from names alone.

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?

There is no tool-level when-to-use/when-not guidance and no named alternative, despite several plausible siblings (override_account_balance for balance edits, delete_account, reorder_accounts). The caution note on 'balance' hints at constraints but is not routing guidance. Usage must be inferred entirely from the parameter list.

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