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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds real behavioral context beyond that: each item carries a confidence label (scheduled, recurring_detected, estimated) and, importantly, that 'each kind shows only where this connection can see its data' — a visibility/permission constraint the agent cannot infer from annotations or schema.

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 dense sentences, with the core purpose front-loaded before the kind enumeration. The long middle list of kinds is justified by the lack of enum descriptions in the schema, though it reads as a run-on and slightly dilutes the opening.

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?

With no output schema, the description correctly describes returned fields (date, amount, confidence) and the visibilty caveat, which is what an agent needs to interpret results. It omits the days default/cap and any note on ordering or volume, leaving minor gaps for a forecast tool.

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 coverage is only 33% (only 'company' is documented in-schema), so the description has to carry weight. It clarifies 'next N days', maps the kinds values to human terms (card and loan minimum payments for payment_of card or loan), and explains the confidence vocabulary. It does not mention the default of 30 days or the 180-day cap, so it is not fully compensating, but it materially exceeds the schema.

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 names a concrete resource (a cash calendar of upcoming money in and out) and enumerates exactly what appears in it: bills, payroll, subscriptions, expected income, taxes, card/loan minimums, bucket schedules. That enumeration separates it cleanly from siblings like list_recurring, get_liabilities and query_transactions, which an agent could otherwise confuse it with.

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 scope ('next N days', a forward-looking cash calendar) implies when the tool is appropriate for planning, but there is no explicit when-to-use/when-not-to-use guidance and no named alternative such as list_recurring or get_liabilities for agents that want raw recurring definitions rather than a forecast.

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