Surfil

Cut costs with Cap

Cap is the cost stage of the pipeline. It measures what each request really needed - prefix-cache alignment, redundant context, model fit - on your own traffic, then signs the measured savings as a receipt you can verify.

Prerequisite: Surfil installed and your device linked - see the Quickstart.

When to use this

When your agent bill is growing and you want a number you can defend: not a vendor projection, but before/after measurement on the traffic your team actually ran.

Steps

  1. Work normally for a representative stretch - Cap measures real sessions, so the input is just your usual week.
  2. Run the audit:
$ surfil audit
✓ measured before/after on your traffic · recoverable tokens reported
✓ receipt signed (Ed25519)

The audit compares token usage before and after Cap's optimizations and signs the measured result. That signed receipt is the deliverable - one Credit, one signed output.

Reading the numbers honestly

  • Savings are reported in tokens - the unit where the measurement is a fact - never an invented dollar figure.
  • There is no headline percentage: your receipt shows what was actually measured on your traffic, which is the only number that means anything.
  • Nothing is "certified". Every claim traces to a signed, measured fact.

How you know it worked

  • surfil audit completes with a signed receipt id.
  • surfil verify <receipt-id> reports VALID - offline, no account needed.
  • Your provider bill over the same window moves consistently with the token delta the receipt records.
A near-zero measured saving is a valid, honest result - it means your setup was already efficient (good prefix-cache discipline, lean context). Cap signs what it measures either way; it never inflates a floor to make a sale.