Simon Willison’s Weblog

New OpenAI feature: Predicted Outputs (via) Interesting new ability of the OpenAI API - the first time I've seen this from any vendor.

If you know your prompt is mostly going to return the same content - you're requesting an edit to some existing code, for example - you can now send that content as a "prediction" and have GPT-4o or GPT-4o mini use that to accelerate the returned result.

OpenAI's documentation says:

When providing a prediction, any tokens provided that are not part of the final completion are charged at completion token rates.

I initially misunderstood this as meaning you got a price reduction in addition to the latency improvement, but that's not the case: in the best possible case it will return faster and you won't be charged anything extra over the expected cost for the prompt, but the more it differs from your prediction the more extra tokens you'll be billed for.

I ran the example from the documentation both with and without the prediction and got these results. Without the prediction:

"usage": {
  "prompt_tokens": 150,
  "completion_tokens": 118,
  "total_tokens": 268,
  "completion_tokens_details": {
    "accepted_prediction_tokens": 0,
    "audio_tokens": null,
    "reasoning_tokens": 0,
    "rejected_prediction_tokens": 0
  }

That took 5.2 seconds and cost 0.1555 cents.

With the prediction:

"usage": {
  "prompt_tokens": 166,
  "completion_tokens": 226,
  "total_tokens": 392,
  "completion_tokens_details": {
    "accepted_prediction_tokens": 49,
    "audio_tokens": null,
    "reasoning_tokens": 0,
    "rejected_prediction_tokens": 107
  }

That took 3.3 seconds and cost 0.2675 cents.

Further details from OpenAI's Steve Coffey:

We are using the prediction to do speculative decoding during inference, which allows us to validate large batches of the input in parallel, instead of sampling token-by-token!

[...] If the prediction is 100% accurate, then you would see no cost difference. When the model diverges from your speculation, we do additional sampling to “discover” the net-new tokens, which is why we charge rejected tokens at completion time rates.

# 4th November 2024, 11:55 pm / openai, llms, ai, generative-ai, llm-pricing

Claude Token Counter. Anthropic released a token counting API for Claude a few days ago.

I built this tool for running prompts, images and PDFs against that API to count the tokens in them.

The API is free (albeit rate limited), but you'll still need to provide your own API key in order to use it.

Here's the source code. I built this using two sessions with Claude - one to build the initial tool and a second to add PDF and image support. That second one is a bit of a mess - it turns out if you drop an HTML file onto a Claude conversation it converts it to Markdown for you, but I wanted it to modify the original HTML source.

The API endpoint also allows you to specify a model, but as far as I can tell from running some experiments the token count was the same for Haiku, Opus and Sonnet 3.5.

# 2nd November 2024, 6:52 pm / anthropic, claude, ai-assisted-programming, tools, generative-ai, ai, llms, claude-artifacts, llm-pricing

Running prompts against images and PDFs with Google Gemini. New TIL. I've been experimenting with the Google Gemini APIs for running prompts against images and PDFs (in preparation for finally adding multi-modal support to LLM) - here are my notes on how to send images or PDF files to their API using curl and the base64 -i macOS command.

I figured out the curl incantation first and then got Claude to build me a Bash script that I can execute like this:

prompt-gemini 'extract text' example-handwriting.jpg

Playing with this is really fun. The Gemini models charge less than 1/10th of a cent per image, so it's really inexpensive to try them out.

# 23rd October 2024, 6:25 pm / vision-llms, gemini, llm, bash, ai, llms, ai-assisted-programming, google, generative-ai, ocr, projects, llm-pricing

Gemini 1.5 Flash-8B is now production ready (via) Gemini 1.5 Flash-8B is "a smaller and faster variant of 1.5 Flash" - and is now released to production, at half the price of the 1.5 Flash model.

It's really, really cheap:

• $0.0375 per 1 million input tokens on prompts <128K
• $0.15 per 1 million output tokens on prompts <128K
• $0.01 per 1 million input tokens on cached prompts <128K

Prices are doubled for prompts longer than 128K.

I believe images are still charged at a flat rate of 258 tokens, which I think means a single non-cached image with Flash should cost 0.00097 cents - a number so tiny I'm doubting if I got the calculation right.

OpenAI's cheapest model remains GPT-4o mini, at $0.15/1M input - though that drops to half of that for reused prompt prefixes thanks to their new prompt caching feature (or by half if you use batches, though those can’t be combined with OpenAI prompt caching. Gemini also offer half-off for batched requests).

Anthropic's cheapest model is still Claude 3 Haiku at $0.25/M, though that drops to $0.03/M for cached tokens (if you configure them correctly).

I've released llm-gemini 0.2 with support for the new model:

llm install -U llm-gemini
llm keys set gemini
# Paste API key here
llm -m gemini-1.5-flash-8b-latest "say hi"

# 3rd October 2024, 8:16 pm / vision-llms, gemini, anthropic, openai, ai, llms, google, generative-ai, llm, llm-pricing

Prompt caching with Claude (via) The Claude API now supports prompt caching, allowing you to mark reused portions of long prompts (like a large document provided as context). Claude will cache these for up to five minutes, and any prompts within that five minutes that reuse the context will be both significantly faster and will be charged at a significant discount: ~10% of the cost of sending those uncached tokens.

Writing to the cache costs money. The cache TTL is reset every time it gets a cache hit, so any application running more than one prompt every five minutes should see significant price decreases from this. If you app prompts less than once every five minutes you'll be losing money.

This is similar to Google Gemini's context caching feature, but the pricing model works differently. Gemini charge $4.50/million tokens/hour for their caching (that's for Gemini 1.5 Pro - Gemini 1.5 Flash is $1/million/hour), for a quarter price discount on input tokens (see their pricing).

Claude’s implementation also appears designed to help with ongoing conversations. Using caching during an individual user’s multi-turn conversation - where a full copy of the entire transcript is sent with each new prompt - could help even for very low traffic (or even single user) applications.

Here's the full documentation for the new Claude caching feature, currently only enabled if you pass "anthropic-beta: prompt-caching-2024-07-31" as an HTTP header.

Interesting to note that this caching implementation doesn't save on HTTP overhead: if you have 1MB of context you still need to send a 1MB HTTP request for every call. I guess the overhead of that HTTP traffic is negligible compared to the overhead of processing those tokens once they arrive.

One minor annoyance in the announcement for this feature:

Detailed instruction sets: Share extensive lists of instructions, procedures, and examples to fine-tune Claude's responses. [...]

I wish Anthropic wouldn't use the term "fine-tune" in this context (they do the same thing in their tweet). This feature is unrelated to model fine-tuning (a feature Claude provides via AWS Bedrock). People find this terminology confusing already, frequently misinterpreting "fine-tuning" as being the same thing as "tweaking your prompt until it works better", and Anthropic's language here doesn't help.

# 14th August 2024, 5:07 pm / gemini, prompt-engineering, anthropic, claude, generative-ai, ai, llms, llm-pricing

Gemini 1.5 Flash price drop (via) Google Gemini 1.5 Flash was already one of the cheapest models, at 35c/million input tokens. Today they dropped that to just 7.5c/million (and 30c/million) for prompts below 128,000 tokens.

The pricing war for best value fast-and-cheap model is red hot right now. The current most significant offerings are:

• Google's Gemini 1.5 Flash: 7.5c/million input, 30c/million output (below 128,000 input tokens)
• OpenAI's GPT-4o mini: 15c/million input, 60c/million output
• Anthropic's Claude 3 Haiku: 25c/million input, $1.25/million output

Or you can use OpenAI's GPT-4o mini via their batch API, which halves the price (resulting in the same price as Gemini 1.5 Flash) in exchange for the results being delayed by up to 24 hours.

Worth noting that Gemini 1.5 Flash is more multi-modal than the other models: it can handle text, images, video and audio.

Also in today's announcement:

PDF Vision and Text understanding

The Gemini API and AI Studio now support PDF understanding through both text and vision. If your PDF includes graphs, images, or other non-text visual content, the model uses native multi-modal capabilities to process the PDF. You can try this out via Google AI Studio or in the Gemini API.

This is huge. Most models that accept PDFs do so by extracting text directly from the files (see previous notes), without using OCR. It sounds like Gemini can now handle PDFs as if they were a sequence of images, which should open up much more powerful general PDF workflows.

Update: it turns out Gemini also has a 50% off batch mode, so that’s 3.25c/million input tokens for batch mode 1.5 Flash!

# 8th August 2024, 10:27 pm / gemini, anthropic, claude, openai, ai, llms, google, generative-ai, vision-llms, pdf, llm-pricing

GPT-4o mini. I've been complaining about how under-powered GPT 3.5 is for the price for a while now (I made fun of it in a keynote a few weeks ago).

GPT-4o mini is exactly what I've been looking forward to.

It supports 128,000 input tokens (both images and text) and an impressive 16,000 output tokens. Most other models are still ~4,000, and Claude 3.5 Sonnet got an upgrade to 8,192 just a few days ago. This makes it a good fit for translation and transformation tasks where the expected output more closely matches the size of the input.

OpenAI show benchmarks that have it out-performing Claude 3 Haiku and Gemini 1.5 Flash, the two previous cheapest-best models.

GPT-4o mini is 15 cents per million input tokens and 60 cents per million output tokens - a 60% discount on GPT-3.5, and cheaper than Claude 3 Haiku's 25c/125c and Gemini 1.5 Flash's 35c/70c. Or you can use the OpenAI batch API for 50% off again, in exchange for up-to-24-hours of delay in getting the results.

It's also worth comparing these prices with GPT-4o's: at $5/million input and $15/million output GPT-4o mini is 33x cheaper for input and 25x cheaper for output!

OpenAI point out that "the cost per token of GPT-4o mini has dropped by 99% since text-davinci-003, a less capable model introduced in 2022."

One catch: weirdly, the price for image inputs is the same for both GPT-4o and GPT-4o mini - Romain Huet says:

The dollar price per image is the same for GPT-4o and GPT-4o mini. To maintain this, GPT-4o mini uses more tokens per image.

Also notable:

GPT-4o mini in the API is the first model to apply our instruction hierarchy method, which helps to improve the model's ability to resist jailbreaks, prompt injections, and system prompt extractions.

My hunch is that this still won't 100% solve the security implications of prompt injection: I imagine creative enough attackers will still find ways to subvert system instructions, and the linked paper itself concludes "Finally, our current models are likely still vulnerable to powerful adversarial attacks". It could well help make accidental prompt injection a lot less common though, which is certainly a worthwhile improvement.

# 18th July 2024, 6:11 pm / vision-llms, generative-ai, openai, ai, llms, prompt-injection, llm-pricing

Context caching for Google Gemini (via) Another new Gemini feature announced today. Long context models enable answering questions against large chunks of text, but the price of those long prompts can be prohibitive - $3.50/million for Gemini Pro 1.5 up to 128,000 tokens and $7/million beyond that.

Context caching offers a price optimization, where the long prefix prompt can be reused between requests, halving the cost per prompt but at an additional cost of $4.50 / 1 million tokens per hour to keep that context cache warm.

Given that hourly extra charge this isn't a default optimization for all cases, but certain high traffic applications might be able to save quite a bit on their longer prompt systems.

It will be interesting to see if other vendors such as OpenAI and Anthropic offer a similar optimization in the future.

Update 14th August 2024: Anthropic's Claude now has its own version of prompt caching.

# 14th May 2024, 8:42 pm / gemini, prompt-engineering, google, generative-ai, ai, llms, llm-pricing

Gemini 1.5 Pro public preview (via) Huge release from Google: Gemini 1.5 Pro—the GPT-4 competitive model with the incredible 1 million token context length—is now available without a waitlist in 180+ countries (including the USA but not Europe or the UK as far as I can tell)... and the API is free for 50 requests/day (rate limited to 2/minute).

Beyond that you’ll need to pay—$7/million input tokens and $21/million output tokens, which is slightly less than GPT-4 Turbo and a little more than Claude 3 Sonnet.

They also announced audio input (up to 9.5 hours in a single prompt), system instruction support and a new JSON mod.

# 10th April 2024, 2:38 am / gemini, google, generative-ai, ai, llms, vision-llms, llm-pricing

The new Claude 3 model family from Anthropic. Claude 3 is out, and comes in three sizes: Opus (the largest), Sonnet and Haiku.

Claude 3 Opus has self-reported benchmark scores that consistently beat GPT-4. This is a really big deal: in the 12+ months since the GPT-4 release no other model has consistently beat it in this way. It’s exciting to finally see that milestone reached by another research group.

The pricing model here is also really interesting. Prices here are per-million-input-tokens / per-million-output-tokens:

Claude 3 Opus: $15 / $75
Claude 3 Sonnet: $3 / $15
Claude 3 Haiku: $0.25 / $1.25

All three models have a 200,000 length context window and support image input in addition to text.

Compare with today’s OpenAI prices:

GPT-4 Turbo (128K): $10 / $30
GPT-4 8K: $30 / $60
GPT-4 32K: $60 / $120
GPT-3.5 Turbo: $0.50 / $1.50

So Opus pricing is comparable with GPT-4, more than GPT-4 Turbo and significantly cheaper than GPT-4 32K... Sonnet is cheaper than all of the GPT-4 models (including GPT-4 Turbo), and Haiku (which has not yet been released to the Claude API) will be cheaper even than GPT-3.5 Turbo.

It will be interesting to see if OpenAI respond with their own price reductions.

# 4th March 2024, 6:34 pm / anthropic, claude, generative-ai, openai, gpt-4, ai, llms, vision-llms, llm-pricing