And since the cloud providers don't have the problem in your first sentence (even if the customers pre-paid, they're still easily identifiable), they never bothered to implement the solution from your last sentence. But seriously, the problem of accurate, real-time billing is not a new one, and it's been solved before several times already (e.g. RADIUS/Diameter of dial-up ISPs)."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_Joker_vD","story_49949235"],"author":"Joker_vD","comment_text":"> This worked for post-paid, when customers were assumed to be trusted, and legal sanctions could be levied against those who refused to pay their bill. However, this approach broke down when prepaid plans were introduced. This led to the invention of CAMEL, which is basically a realtime protocol which lets the MSC ask the HLR whether a given call was permitted or not.
And since the cloud providers don't have the problem in your first sentence (even if the customers pre-paid, they're still easily identifiable), they never bothered to implement the solution from your last sentence. But seriously, the problem of accurate, real-time billing is not a new one, and it's been solved before several times already (e.g. RADIUS/Diameter of dial-up ISPs).","created_at":"2026-10-06T11:15:50Z","created_at_i":1791285350,"objectID":"49976851","parent_id":49975147,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-06T11:19:01Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"stuaxo"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Yeah I want the hard budget limit, I absolutely don't want a suprise mega bill and as such stay away from cloud services especially AWS because it's hard to reason about where it will come from."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_stuaxo","story_49949235"],"author":"stuaxo","comment_text":"Yeah I want the hard budget limit, I absolutely don't want a suprise mega bill and as such stay away from cloud services especially AWS because it's hard to reason about where it will come from.","created_at":"2026-10-06T10:03:47Z","created_at_i":1791281027,"objectID":"49976377","parent_id":49950196,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-06T10:05:30Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"miki123211"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Telcos did work like that (especially in roaming scenarios).
Your MSC (roughly the thing that people in your geographic area connect to) would talk to your HLR (the place where your records are stored specifically, regardless of current location) to authenticate you and make sure you're a real subscriber, but it wouldn't necessarily do so before every single call. At the end of some billing period, the operator whose services you've used (MSC owner) would send billing records (using the TAP format) to your operator, usually via FTP or similar, and your operator would use them to send you a bill.
This worked for post-paid, when customers were assumed to be trusted, and legal sanctions could be levied against those who refused to pay their bill. However, this approach broke down when prepaid plans were introduced. This led to the invention of CAMEL, which is basically a realtime protocol which lets the MSC ask the HLR whether a given call was permitted or not."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_miki123211","story_49949235"],"author":"miki123211","children":[49976851],"comment_text":"Telcos did work like that (especially in roaming scenarios).
Your MSC (roughly the thing that people in your geographic area connect to) would talk to your HLR (the place where your records are stored specifically, regardless of current location) to authenticate you and make sure you're a real subscriber, but it wouldn't necessarily do so before every single call. At the end of some billing period, the operator whose services you've used (MSC owner) would send billing records (using the TAP format) to your operator, usually via FTP or similar, and your operator would use them to send you a bill.
This worked for post-paid, when customers were assumed to be trusted, and legal sanctions could be levied against those who refused to pay their bill. However, this approach broke down when prepaid plans were introduced. This led to the invention of CAMEL, which is basically a realtime protocol which lets the MSC ask the HLR whether a given call was permitted or not.","created_at":"2026-10-06T07:00:39Z","created_at_i":1791270039,"objectID":"49975147","parent_id":49952394,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-06T11:16:30Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"incee"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"I have relied on budgets a lot and when I get annoyed and enable auto top-off, my adhd-addled brain blew $40 on tokens yesterday instead of /model cheapseats"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_incee","story_49949235"],"author":"incee","comment_text":"I have relied on budgets a lot and when I get annoyed and enable auto top-off, my adhd-addled brain blew $40 on tokens yesterday instead of /model cheapseats","created_at":"2026-10-05T23:09:54Z","created_at_i":1791241794,"objectID":"49972029","parent_id":49949235,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T23:12:45Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"yencabulator"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"> There's always a sensible upper limit to any operation.
Ooh. It could even literally be "hard limit is 3x of previous month's bill", and you can adjust the multiplier.
That's much less likely to be set, forgotten, and gotten limited by, but it's unlikely to bankrupt customers."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_yencabulator","story_49949235"],"author":"yencabulator","comment_text":"> There's always a sensible upper limit to any operation.
Ooh. It could even literally be "hard limit is 3x of previous month's bill", and you can adjust the multiplier.
That's much less likely to be set, forgotten, and gotten limited by, but it's unlikely to bankrupt customers.","created_at":"2026-10-05T23:07:55Z","created_at_i":1791241675,"objectID":"49972016","parent_id":49951026,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T23:12:45Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"foldr"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Do you have any evidence that AWS makes a significant amount of money by charging for accidental usage? Or is this just general cynicism?"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_foldr","story_49949235"],"author":"foldr","comment_text":"Do you have any evidence that AWS makes a significant amount of money by charging for accidental usage? Or is this just general cynicism?","created_at":"2026-10-05T11:31:19Z","created_at_i":1791199879,"objectID":"49963493","parent_id":49956968,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T11:35:42Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"gewetensleegte"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"just like when we used to have this problem before LLMs, we hired a surprisingly capable junior coder, give them access to all our systems and bank accounts and next morning we'd be bankrupt
weird, that"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_gewetensleegte","story_49949235"],"author":"gewetensleegte","comment_text":"just like when we used to have this problem before LLMs, we hired a surprisingly capable junior coder, give them access to all our systems and bank accounts and next morning we'd be bankrupt
weird, that","created_at":"2026-10-05T10:45:43Z","created_at_i":1791197143,"objectID":"49963161","parent_id":49949235,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T10:48:27Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"watwut"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Ignored alert works exactly as the provider wants it to work. It makes them earn more money.
It works best when coupled with spam of other irrelevant alerts, to maximize the chance of higher earnings."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_watwut","story_49949235"],"author":"watwut","comment_text":"Ignored alert works exactly as the provider wants it to work. It makes them earn more money.
It works best when coupled with spam of other irrelevant alerts, to maximize the chance of higher earnings.","created_at":"2026-10-05T10:07:56Z","created_at_i":1791194876,"objectID":"49962874","parent_id":49952942,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-07T17:33:36Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"afiori"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"loadshedding is based on each load having an associated priority"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_afiori","story_49949235"],"author":"afiori","comment_text":"loadshedding is based on each load having an associated priority","created_at":"2026-10-05T08:08:51Z","created_at_i":1791187731,"objectID":"49962009","parent_id":49953279,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T08:10:58Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"knollimar"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"They switched from post paid billing with shitty delayed caps to prepaid but the prepaid expires after a year\u2026"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_knollimar","story_49949235"],"author":"knollimar","comment_text":"They switched from post paid billing with shitty delayed caps to prepaid but the prepaid expires after a year\u2026","created_at":"2026-10-05T06:10:51Z","created_at_i":1791180651,"objectID":"49961225","parent_id":49951849,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T08:06:57Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"rusebor"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Interestingly that linux kernel does not have caps for cpu in terms of instructions."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_rusebor","story_49949235"],"author":"rusebor","comment_text":"Interestingly that linux kernel does not have caps for cpu in terms of instructions.","created_at":"2026-10-05T05:55:54Z","created_at_i":1791179754,"objectID":"49961148","parent_id":49949235,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T06:00:26Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"soltanov"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Email alerts arrive too late when usage grows quickly."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_soltanov","story_49949235"],"author":"soltanov","comment_text":"Email alerts arrive too late when usage grows quickly.","created_at":"2026-10-05T04:04:22Z","created_at_i":1791173062,"objectID":"49960549","parent_id":49950196,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T04:04:57Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"toast0"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"> Why is egress more expensive than ingress in clouds? To lock in users.
Eh... Bandwidth contracts are almost always billed only in the dominant direction. Very few cloud applications are inbound dominant. There's no need to bill for inbound traffic.
I personally find the cloud bandwidth prices pretty high, and I assume that's where they make up for difficult to account for costs, but not charging for inbound is totally reasonable."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_toast0","story_49949235"],"author":"toast0","comment_text":"> Why is egress more expensive than ingress in clouds? To lock in users.
Eh... Bandwidth contracts are almost always billed only in the dominant direction. Very few cloud applications are inbound dominant. There's no need to bill for inbound traffic.
I personally find the cloud bandwidth prices pretty high, and I assume that's where they make up for difficult to account for costs, but not charging for inbound is totally reasonable.","created_at":"2026-10-05T03:19:21Z","created_at_i":1791170361,"objectID":"49960335","parent_id":49951439,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-05T03:22:56Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"trollbridge"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Power companies provide meters with real time transparency."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_trollbridge","story_49949235"],"author":"trollbridge","comment_text":"Power companies provide meters with real time transparency.","created_at":"2026-10-04T22:38:31Z","created_at_i":1791153511,"objectID":"49958667","parent_id":49952741,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-08T22:23:57Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"thatsit"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"Well, we don\u2019t need to reinvent pre-paid services, just because it\u2019s \u201eAI\u201c"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_thatsit","story_49949235"],"author":"thatsit","comment_text":"Well, we don\u2019t need to reinvent pre-paid services, just because it\u2019s \u201eAI\u201c","created_at":"2026-10-04T21:05:30Z","created_at_i":1791147930,"objectID":"49957859","parent_id":49949235,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-04T21:10:57Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"HamadMalikKhan"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"This, plus the implementation on the AI providers' side is still choppy. I remember one of our implementations had a $500 limit on OpenAI with auto-recharge enabled. It burned through $600 despite the lower limit.
You can be down serious money even with a limit set."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_HamadMalikKhan","story_49949235"],"author":"HamadMalikKhan","comment_text":"This, plus the implementation on the AI providers' side is still choppy. I remember one of our implementations had a $500 limit on OpenAI with auto-recharge enabled. It burned through $600 despite the lower limit.
You can be down serious money even with a limit set.","created_at":"2026-10-04T21:01:12Z","created_at_i":1791147672,"objectID":"49957807","parent_id":49949235,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-04T21:05:41Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"hashstring"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"yolo in dev can still lead to high bills"},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_hashstring","story_49949235"],"author":"hashstring","comment_text":"yolo in dev can still lead to high bills","created_at":"2026-10-04T20:26:21Z","created_at_i":1791145581,"objectID":"49957477","parent_id":49950196,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-04T20:28:56Z"},{"_highlightResult":{"author":{"matchLevel":"none","matchedWords":[],"value":"DANmode"},"comment_text":{"matchLevel":"none","matchedWords":[],"value":"It doesn\u2019t matter who is offering the service, or even if it\u2019s free: HN will criticize it.
Good."},"story_title":{"matchLevel":"none","matchedWords":[],"value":"We're going to need default hard budget caps on pretty much everything"},"story_url":{"matchLevel":"none","matchedWords":[],"value":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/"}},"_tags":["comment","author_DANmode","story_49949235"],"author":"DANmode","comment_text":"It doesn\u2019t matter who is offering the service, or even if it\u2019s free: HN will criticize it.
Good.","created_at":"2026-10-04T20:08:47Z","created_at_i":1791144527,"objectID":"49957333","parent_id":49949556,"story_id":49949235,"story_title":"We're going to need default hard budget caps on pretty much everything","story_url":"https://simonwillison.net/2026/Oct/3/default-hard-budget-caps/","updated_at":"2026-10-04T20:13:11Z"}],"hitsPerPage":20,"nbHits":312,"nbPages":16,"page":0,"params":"tags=story_49949235&advancedSyntax=true&analyticsTags=backend","processingTimeMS":1,"processingTimingsMS":{"_request":{"queue":254,"roundTrip":15},"total":1},"query":"","serverTimeMS":256}