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Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

prompt-caching.ai

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Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#11

Post by ermis »

somesnm wrote: post #4

Hasn't this been largely solved by auto-caching introduced recently by Anthropic, where you pass "cache_control": {"type": "ephemeral"} in your request and it puts breakpoints automatically? https://platform.claude.com/docs/en/build-with-claude/prompt...

[flagged]

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#12

Post by [deleted] »

katspaugh wrote: post #10

> This plugin is built for developers building their own applications with the Anthropic API. > Important note for Claude Code users: Claude Code already handles prompt caching automatically for its own API calls — system prompts, tool definitions, and conversation history are cached out of the box. Source: their GitHub

[deleted]

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#13

Post by stingraycharles »

ermis wrote: post #11
somesnm wrote: post #4

Hasn't this been largely solved by auto-caching introduced recently by Anthropic, where you pass "cache_control": {"type": "ephemeral"} in your request and it puts breakpoints automatically? https://platform.claude.com/docs/en/build-with-claude/prompt...

[flagged]

Please don’t use AI for writing comments.

Also, what this adds is mostly overhead at the wrong level of abstraction, not visibility.

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#14

Post by ermis »

spiderfarmer wrote: post #3

Will this work for Cowork as well?

No. Claude.ai is a consumer product — you have no access to the API layer underneath it. cache_control is an API-level feature only. This plugin works exclusively when you're making direct Anthropic API calls, either through the SDK in your own code or through MCP-compatible clients like Claude Code, Cursor, Windsurf, etc.

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#15

Post by stingraycharles »

philipp-gayret wrote: post #8
somesnm wrote: post #4

Hasn't this been largely solved by auto-caching introduced recently by Anthropic, where you pass "cache_control": {"type": "ephemeral"} in your request and it puts breakpoints automatically? https://platform.claude.com/docs/en/build-with-claude/prompt...

Looking at my own usage with claude code out of the box and nothing special around caching set up. For this month according to ccusage I have in tokens 0.2M input, 0.6M output, 10M cache create, 311M cache read for 322M total tokens. Seems to me that it caches out of the box quite heavily, but if I can trim my usage somehow with these kind of tools I'd love to know.

This is not about caching things for stuff that others built, it’s solely to modify code that you’re writing that will use Anthropic’s API endpoints.

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#16

Post by gostsamo »

somesnm wrote: post #4

Hasn't this been largely solved by auto-caching introduced recently by Anthropic, where you pass "cache_control": {"type": "ephemeral"} in your request and it puts breakpoints automatically? https://platform.claude.com/docs/en/build-with-claude/prompt...

It is answered in the FAQ.

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#17

Post by fschuett »

Slightly off-topic, but I recently tested some tool and it turns out Opus is far cheaper than Sonnet, because it produces way less output tokens and those are what's expensive. It's also much slower than Opus (I did 9 runs to compare Haiku, Sonnet and Opus on the same problem). I also thought "oh, Sonnet is more light-weight and cheaper than Opus", no, that's actually just marketing.

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#18

Post by adi_pradhan »

This is applicable only to the API from what i understand. Since claude code already caches quite aggressively (try npx ccusage)

Also the anthropic API did already introduce prompt-caching https://platform.claude.com/docs/en/build-with-claude/prompt...

What is new here?

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#19

Post by numlocked »

As per its own FAQ this plugin is out of date and doesn’t actually do anything incremental re:caching:

> "Hasn't Anthropic's new auto-caching feature solved this?"

> Largely, yes — Anthropic's automatic caching (passing "cache_control": {"type": "ephemeral"} at the top level) handles breakpoint placement automatically now. This plugin predates that feature and originally filled that gap.

Re: Prompt-caching – auto-injects Anthropic cache breakpoints (90% token savings)

#20

Post by orphea »

numlocked wrote: post #19

As per its own FAQ this plugin is out of date and doesn’t actually do anything incremental re:caching: > "Hasn't Anthropic's new auto-caching feature solved this?" > Largely, yes — Anthropic's automatic caching (passing "cache_control": {"type": "ephemeral"} at the top level) handles breakpoint placement automatically now. This plugin predates that feature and originally filled that gap.

I don't understand and I'm curious, why a dead on arrival open source tool needs a separate domain?

  Domain Name: prompt-caching.ai
  Updated Date: 2026-03-12T20:31:44Z
  Creation Date: 2026-03-12T20:27:35Z
  Registry Expiry Date: 2028-03-12T20:27:35Z
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