Budget/Spend Approval Router: Send Every Spend Request to the Right Approver, Automatically
Turn a spend-request form into a governed routing tool — it checks the request against remaining project budget, routes it to the right approver(s) by amount and category threshold, records the decision, and only commits approved spend against budget or exports it to finance.
A logged-in tool where anyone submits a spend request, the tool checks it against the project's remaining budget, routes it to the threshold-appropriate approver(s), the approver(s) approve or reject, and only an approved request is committed against budget and exported to finance — with the requester notified and a full audit trail.
Before you start
- A Supabase account (free)
- A Vercel account (free)
- A Resend account (free)
- Your project-budget list with remaining balances (CSV or Google Sheet)
- Your approval-threshold rules (who approves what, by amount and category)
- Claude Code or any AI coding agent
The problem this kills
Spend requests live in the worst possible places: an email to a manager who's on vacation, a Slack message that scrolls away, a form that lands in a shared inbox nobody owns. Someone approves a $4,000 purchase by replying "ok" — but nobody checked whether the project still has $4,000 left, nobody knows that this category needed a director's sign-off, and three weeks later finance finds two people approved the same request twice.
The rules everyone "knows" — PM can approve under $5k, director up to $25k, VP above that — live in a wiki page or a person's head. They don't get applied consistently, they don't get applied against the remaining budget, and they leave no record. When the budget overruns, there's no clean answer to "who approved this, against what balance, and on what date?"
A spend-approval router fixes the routing and the governance in one tool. The request is checked against real remaining budget, sent to exactly the right approver(s) for its size and type, decided on the record, and only committed once — never twice.
What you'll build
A simple internal web app for your project teams and finance partners. Anyone on the team submits a spend request — project, category, amount, vendor, description. The tool looks up that project's remaining budget, warns immediately if the request would blow the balance, and routes it by your threshold rules: a PM signs off small requests, a director the mid-sized ones, a VP the large ones — with multi-level routing when a request needs more than one approval.
The approver(s) see the request with the budget context attached and approve or reject it. Only an approved request is committed against the project's remaining budget and exported to finance — never a pending or rejected one, and never twice. The requester is notified the moment a decision lands, and every step is on the record.
What's inside the Implementation Plan
The downloadable plan is a step-by-step file you paste into an AI coding agent. It opens by interviewing you about your business — your real approval thresholds and category rules, how your project-budget list is shaped and named, who the approvers are at each level, whether some categories or vendors need extra sign-off, and the messy exceptions (split-funded projects, emergency spend, requests that span two budgets). It reads a short tailored spec back to you and waits for your thumbs-up before it builds anything, so the router matches your delegation-of-authority rules — not a generic template.
From there it walks the agent through the data model, the budget import, the spend-request form, the budget check, the threshold routing engine (including multi-level), the approval gate, the commit-once-against-budget logic, the requester notifications, and the finance CSV export. Every step ends with a ready-to-copy prompt. There's a full "No API yet?" path that uses a Google Sheet / CSV for budgets and rules and produces a clean approved-spend CSV for finance — so you can build and run the whole thing this weekend regardless of what ERP or finance system you're on.
The governance it includes (this is the point)
This is a spend-control tool, so the controls aren't optional. The plan builds in login so only your team can use it, row-level security so people only ever see their own organization's projects and requests, a complete audit trail of who submitted, who routed, and who approved each request, a hard human-approval gate so no spend is ever committed against budget or sent to finance until the threshold-appropriate approver(s) sign off, and duplicate guards so the same request can't be processed — or committed — twice.
Who it's for
Project managers, project sponsors, finance partners, and PMO controllers — anyone who has to keep project spend inside an approved budget and apply real delegation-of-authority rules. If you can explain who approves what and where your remaining budget lives, you can build this.
You've got this — start with the plan, paste the first prompt, and answer the interview. You'll have your first request routing to the right approver before the weekend's out.