Legal Bill Auditor
Reads the law firm's invoice against the guidelines you agreed
- 8hard rules
- Things it must never do, enforced in every run
- 5handover rules
- Conditions where it stops and gives the work to a person
- 10output fields
- A structured result, not a paragraph you have to re-read
- ≤8steps per run
- Bounded work: at most 6 tool calls, enforced by the runtime
Read-only by design. This agent has no path to sending, spending, publishing or committing anything. Where that limit is the product, removing it would remove the reason to trust the output.
Overview
In-house legal teams negotiate billing guidelines carefully — who may work on a matter, what rates apply, what is billable, what needs approval — and then receive invoices nobody has time to read against them. A general counsel with a live dispute is not going to spend an afternoon checking whether a partner billed 0.3 hours for reading an email.
So the same overruns recur, and they are almost never dishonest. They are the predictable output of a billing model where time is captured by many people under pressure.
Block billing — several tasks collapsed into one long entry — makes every other check impossible, because you cannot judge whether four hours were reasonable when you cannot see what they were. Timekeepers who are not on the agreed rate card. Partner time on work the guidelines assign to an associate. Several attendees where the guidelines allow one. Administrative time billed as legal time. Rate increases applied without the notice the engagement letter requires.
This agent reads each invoice against the guidelines you already agreed and reports what does not match, with the clause behind it. It is not a judgement about whether work was worth doing — that is legal judgement and it stays with your lawyer. It disputes nothing and pays nothing.
Benefits
Spend controlled without a fight
The guidelines were agreed; this just reads against them.
A pattern to take to the relationship
One recurring overrun is a conversation, not a line query.
Budgets that hold
Because the drift is visible in month one.
What it does
Flags block billing first
Several tasks in one long entry defeats every other check. You cannot judge four hours you cannot see inside.
Checks every timekeeper against the rate card
People appear on matters who were never agreed, at rates that were never agreed.
Finds seniority mismatches
Partner time on work the guidelines assign to an associate, priced at the difference.
Catches duplicate attendance
Three timekeepers at a hearing the guidelines allow one to attend.
Tests rate rises against the engagement letter
Increases applied without the notice the letter requires, often unnoticed for a year.
Judges no legal work
Whether work was worth doing is legal judgement. It checks the bill against what you agreed.
What this changes
What this changes about your week
- It takes over
- Reading counsel invoices line by line against the billing guidelines you negotiated.
- Done today by
- Nobody. A GC with a live dispute has no afternoon for it.
- How often
- Every invoice, in theory.
- Typical manual effort
- Each line needs the guidelines, the rate card and the engagement letter held together.
Why Legal in particular. Block billing collapses several tasks into one entry and defeats every other check — you cannot judge four hours you cannot see inside. And rate rises pass unnoticed for a year.
Runs unattended
Started by you or by an event, and it finishes on its own. Nothing waits for someone to be at a desk.
The same standard every time
The two-hundredth item is held to the bar the first one was. Consistency is the part people cannot sustain.
It cannot act on its own
Legal Bill Auditor has no path to sending, spending or committing. That limit is why its output is safe to act on.
How it runs
This agent runs server-side through the PROMIVO runtime. Each run is logged step by step and every tool call is permission-checked before it executes.
- 1InputValidated against the agent input schema
- 2Modelclaude-opus-5 with automatic fallback
- 3Toolssearch_knowledge, extract_structured_data
- 4PermissionsRuns READ actions automatically; anything higher waits for approval
- 5OutputStructured result matching the output schema
- 6LoggingTokens, duration and every step recorded
Demo
Demo dataIllustrative sample output, abridged.
Input
{
"budget": 240000,
"matter": "Harbour dispute",
"currency": "USD",
"invoices": []
}Output
{
"escalate": true,
"findings": [
{
"type": "off-rate-card-timekeeper",
"hours": 41,
"clause": "Guidelines 2.1 — only timekeepers approved in writing may bill to the matter.",
"detail": "Two timekeepers billed 41 hours between them and appear on no approved list or rate card.",
"amountAtIssue": 16400
},
{
"type": "seniority-mismatch",
"hours": 22.5,
"clause": "Guidelines 3.4 — document review is billed at associate grade or below.",
"detail": "22.5 hours of document review billed at partner rate. Priced at the rate difference, not the full amount.",
"amountAtIssue": 9450
},
{
"type": "unnotified-rate-increase",
"hours": 96,
"clause": "Engagement letter 7.1 — 60 days' written notice of any rate change.",
"detail": "Partner rate moved from 700 to 780 in January. No notice appears in the correspondence supplied.",
"amountAtIssue": 7680
},
{
"type": "duplicate-attendance",
"hours": 13,
"clause": "Guidelines 5.2 — one fee earner attends a hearing unless agreed in advance.",
"detail": "Three timekeepers billed the 14 May hearing.",
"amountAtIssue": 6100
}
],
"disclaimer": "A check of invoices against the guidelines you agreed. Nothing has been disputed, reduced, approved or paid, no firm contacted, no assessment made of whether any legal work was necessary or well done, and every finding is a question for the firm rather than a proven overcharge.",
"blockBilling": {
"note": "Clause 4.2 requires tasks to be billed separately. A quarter of billed time arrives as entries like 'Review documents; correspondence; call with client; consider strategy — 6.4 hours'. Nothing else in this report can be checked against those hours.",
"hours": 118,
"entries": 34,
"shareOfBilledTime": 26.4
},
"totalAtIssue": 39630,
"couldNotCheck": [
"Whether the 118 block-billed hours are reasonable. That is exactly what block billing prevents, and it is the point of the first finding."
],
"budgetPosition": "Billed 218,000 against a 240,000 budget with the trial preparation phase not yet started.",
"guidelinesFound": true,
"escalationReason": "Block billing is 26.4% of billed time, two timekeepers are not on the rate card, and a rate increase appears to have been applied without the notice the engagement letter requires.",
"questionsForTheFirm": [
"Please rebill the block-billed entries as separate tasks, per clause 4.2.",
"Confirm when the two additional timekeepers were approved to the matter, and at what rates.",
"Provide the notice given for the January rate increase."
]
}Requirements
Integrations
No integrations required.
Before you start
- External counsel invoices with line-level narrative, timekeeper, hours and rate
- Your billing guidelines and the engagement letter, in a knowledge base
- The agreed rate card
- Requires the All-Access plan or higher
Use cases
Every invoice, before approval
Where a query still costs nothing.
A matter running over budget
What is driving it, by timekeeper and task.
Panel review
Which firms actually bill to the guidelines.
After a rate negotiation
Whether the agreed rates are the ones being charged.
Pricing
All-Access
Billed monthly through your PROMIVO subscription. Cancel at any time.
Runs consume your plan allowance for agent executions and tokens. See plan limits
FAQ
Does it judge whether the legal work was necessary?
Never. That is legal judgement requiring the full matter context, and it belongs to your lawyer. It checks the bill against the guidelines you agreed.
Does it dispute or reduce invoices?
No. It produces findings and the clause each rests on. Querying a firm's invoice is a relationship conversation, and often the answer is a good one.
Does it read privileged matter content?
It reads narrative lines on invoices, which can describe privileged work. It reports on billing structure and never reproduces the substance of legal advice.
What if we have no written guidelines?
It checks arithmetic, rate consistency, block billing and duplicate attendance, and says the guideline check was not performed. Most of the value needs the guidelines, and that gap is worth knowing.
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