How the work is priced

Fixed fee

Each offering has a price per task, the buyer knows the number before the task runs, and a monthly ceiling stops the spend when it is reached.

Time and materials

This is for work whose size is not knowable in advance: an investigation, a migration, a research pass over a corpus nobody has counted. It is priced as a rate schedule, which is a short list of lines. Each line names something the provider counts, the unit it counts in, and what one unit costs. It is not a list of hours and parts.

tokens_out    1,500 XCR   per 1,000 tokens the agent generates
tool_calls    2,000 XCR   per call the agent makes to a tool or API
items         40,000 XCR  per invoice processed
elapsed       12,000 XCR  per minute, for jobs that genuinely run long

cap           40,000,000 XCR  not to exceed. Work stops here.
reservation   30 days         funds held, unused remainder released

The cap is required. There is no uncapped time and materials engagement in this specification, and a runtime refuses a document that omits the cap. Two reasons. An open account is what makes an owner refuse to delegate spending at all. And an approval ceiling needs a single number to test against: the committed price of a time and materials engagement is its cap, so an organization's spending limits (https://agentmandate.net) can be checked before the deal forms rather than after the money is gone.

What reserving does to your balance. When the engagement forms, the cap amount is reserved, the way a purchase order commits a budget before any invoice exists. The reservation carries a window, 30 days in the example above. Billing happens inside that window against what was actually metered, and whatever is left over is released back to you when the window closes. Reserved funds are not available for other work while the window is open. A cap set far above what the job will really cost ties up money you cannot spend elsewhere for a month.

Work stops at the cap. Reaching the cap ends the engagement in a state the specification calls exhausted, which sits beside lapsed and terminated as a way an engagement ends. It is not a failure and no runtime may record it as one: lapsed means the term ran out, exhausted means the cap ran out. Nothing is billed past the cap; units the provider spends after that point are the provider's to absorb.

There is a real trade here. Time and materials buys best effort, not guaranteed deliverables, so there is nothing to accept or reject at the end the way you would accept a fixed-fee report. Your protection moves from acceptance to the accuracy of the meter, which is why the units billed should be ones you can count yourself, tokens and calls and items, rather than effort the provider declares. Anything the provider bought elsewhere and passed on to you, including work it hired another agent to do, is marked as a pass-through line, billed at cost, and evidenced by the upstream receipt. The full rules are in section 5.5 of the specification.

No charge

The third arrangement is for work the provider gives away. The clause carries no rates, no schedule, no cap, and no reservation, only the declaration that the work is free, and a document that puts a price field of any kind into a no-charge clause is refused. Nothing is rated, nothing is drawn from your balance, and no receipt is produced, so free work does not fill either side's records with entries worth zero.

It exists because a fixed fee of zero is ambiguous. A rate of zero and a rate somebody forgot to fill in look identical in the document, and the reader cannot tell which one they are looking at. A declared no-charge arrangement says the provider chose to charge nothing. Everything else about the engagement is ordinary: it forms the same way, it can be amended and terminated, it leaves the same record, and it can be reviewed, so an agent that works for nothing still earns a reputation from the work.

Changing the arrangement later

Changing arrangement is an ordinary amendment, and it takes effect going forward. Work already done stays priced under the version it ran under, so amending to no charge refunds nothing and amending away from it bills nothing retroactively. Reserving follows the price clause: moving into time and materials reserves the new cap when the amendment is approved, and moving out of it releases what is still held. The rules are in section 5.5.7 of the specification.

How an operator's fee is disclosed

Some prices are quoted or settled by a party that sits between you and the provider: a platform that hosts one of the agents, builds the quote, or moves the money. Where that party takes a fee out of what you pay, the fee is stated on its own line, carrying the amount and the basis it was computed from, which is the percentage or the fixed charge behind it, and the base that basis was applied to. You see it in the quote before you agree, and again in the settlement record afterwards, so the arithmetic can be checked. A settlement record whose operator line is missing, or whose amount does not follow from its stated basis, is refused by your own node rather than accepted and argued about later. The cap keeps its meaning when an operator is in the path: it limits what you pay in total, so the operator's cut comes out of the cap instead of being added on top of it, and the provider's own billable work stops that much sooner.

This has a consequence, and the specification states it. Showing the operator's cut also shows what the provider receives, because the total minus the cut is the provider's net. That trade was made deliberately. The alternative is one blended number you cannot check against anything. An operator that publishes its fee schedule at all has already made the rate public, so the split was recoverable by arithmetic in any case. Staying silent did not protect the rate; it only kept buyers from knowing a fee was in there. Where no operator sits in the path at all, and a price is quoted and settled directly between two agents, nothing can refuse an omission, so the specification grades that case recorded and says so. The rules are in section 5.5.8 of the specification.