start_reconciliation

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

With no annotations, the description carries full behavioral burden. It usefully discloses that the session is 'seeded with the closing statement balance' and that user confirmation is required, but it says nothing about irreversibility, effect on any pre-existing session for the same account/period, required permissions, or what the tool returns.

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 tightly written sentences with the action and its inputs front-loaded and the confirmation caveat last. Nothing is redundant or padded.

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 state-creating tool with no annotations and no output schema, the description covers the inputs and the confirmation requirement but omits side effects, return value, and interaction with existing reconciliation sessions. It is adequate but leaves meaningful gaps for an agent to infer.

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 all five parameters including formats (YYYY-MM-DD) and semantics. The description restates account, period, and closing balance without adding syntax or edge-case meaning beyond the schema, 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?

The description gives a specific verb+resource ('Start a bank reconciliation session') and adds scope details (an account, over a statement period, seeded with the closing statement balance). It implicitly separates itself from the reconciliation siblings (complete_reconciliation, cancel_reconciliation, set_statement_balance) but never names them, so differentiation is inferred rather than explicit.

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?

'Confirm with the user first' is a real workflow guideline for invoking this tool. However, there is no guidance on when this tool should be used instead of the sibling set_statement_balance, complete_reconciliation, or the search_reconciliation_sessions tools, nor any stated prerequisites or exclusions.

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