OpenInvest

place_fund_order

Destructive

Record an off-exchange fund subscription you already placed: deduct ledger cash, track it in transit, and confirm shares when NAV publishes.

Instructions

Record the first leg of an off-exchange fund purchase the user already placed with the fund platform: cash - amount, and the order is tracked as in transit (status.pending_fund_orders). Total assets do not change (the in-transit amount counts at face value), so there is no fake dip between order day and confirmation. Shares arrive when the pricing-day NAV is published: the fund_confirm job confirms automatically, or call confirm_fund_order. Bookkeeping only — openInvest never places orders.

The expected confirm date uses a Monday-Friday calendar (no China holiday table) and a lag by fund type (QDII / FOF are slower, read from the fund's profile); the result says so (calendar, lag_source).

Confirm fund, amount, and order time with the user before calling; this moves ledger cash.

Args: symbol: FUND:<6 digits>. amount: Subscription amount in CNY; must be > 0. currency: Currency of the amount (CNY). order_ts: Order time, ISO 8601 Beijing time (default now). note: Free-text note. idempotency_key: Reuse the same key when retrying this exact call; recorded once.

Returns: order_id, pricing day (nav_date), expected confirm date, and new cash balance, or {"status": "error", "error": ...}.

Input Schema

Name	Required	Description	Default
`note`	No	Free-text note stored with the order and ledger row.
`amount`	Yes	Subscription amount in CNY (cash deducted now); must be > 0.
`symbol`	Yes	Off-exchange China mutual fund: 'FUND:<6-digit code>' (a bare 6-digit code is also accepted).
`currency`	No	Currency of the amount; off-exchange funds are CNY.	CNY
`order_ts`	No	When the order was placed, ISO 8601 in Beijing time (e.g. '2026-10-19T14:30:00'); default now. Before 15:00 on a trading day the order is priced at that day's NAV, otherwise at the next trading day's. Pass the real time when back-filling an order placed earlier.
`idempotency_key`	No	Optional client-generated key (e.g. a UUID4). When retrying this SAME call after a timeout or an unknown result, reuse the same key: the ledger records it once and later calls return {"status": "duplicate"} without touching cash or holdings. Only the key is compared, not the arguments — a different order (other symbol/units/price/amount) needs a new key, or it is silently treated as the retry.

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Addedv0.45.1Oct 19, 2026

TDQS

A4.4/5.0

Behavior5/5

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

Goes well beyond the annotations (readOnlyHint=false, destructiveHint=true) by spelling out the actual ledger effect: cash is deducted now, the in-transit amount counts at face value so total assets don't move and there is no fake dip. It also discloses the confirm-date calendar limitation (Monday–Friday, no China holiday table), the lag_source, and the idempotency-key retry semantics, which is exactly the kind of side-effect detail an agent needs for a mutating tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose and ledger effect, then supporting caveats, then args/returns. Efficient for the amount of information conveyed, though the Returns block is partially redundant given an output schema exists.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutating, non-idempotent bookkeeping tool with 6 params, this covers side effects, timing/NAV rules, confirmation workflow, retry semantics, and the sibling used to confirm. With an output schema present, the extra return-value summary is harmless and nothing an agent needs to invoke it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the schema descriptions are more detailed than the description's Args block (e.g. the 15:00 NAV cutoff and the idempotency-key duplicate behavior live in the schema). The description restates symbol/amount/currency without adding format or edge-case meaning beyond what the schema already provides, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a precise verb+resource ('record the first leg of an off-exchange fund purchase') and immediately draws the boundary that distinguishes it from siblings: 'Bookkeeping only — openInvest never places orders.' An agent can tell it apart from buy/confirm_fund_order/record_execution without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear when-to-use context ('the user already placed' the order, confirm fund/amount/time before calling) and names the alternative path for confirmation (the `fund_confirm` job or `confirm_fund_order`). It stops short of explicitly excluding the look-alike `buy` tool, so routing is good but not exhaustive.

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