标签：#Claude

Of all the things involved in turning a woman's life into a 60-second reel, I assumed that the writing would be the easy part. Surely telling a good story in 150 words is exactly what a large language model should be good at; yet it proved surprisingly difficult. Draft after draft suffered from common AI weaknesses: a tendency to use hyperbole and inspirational language, to generalize, follow generic founder arcs ("built in a basement"), and focus on morbid details. (For this effort, I was using Sonnet 4.6, which I found to be better — more grounded, more true to facts, less inventive — than Opus 4.7 at creating longer bios.) Getting to something publishable took a significant amount of work. That said, the human in this story also found writing good short story arcs surprisingly challenging, so the effort spent on getting the system to do it decently was well worth it. Here's some context, then what I did. I've been publishing short biographies of notable women for a while now, on a website called Tycoona . Why notable women? Because in each field there are so many women who contributed so much and are little known. I've never understood why Corita Kent , the pop-artist nun, isn't as famous as Andy Warhol, why Hetty Green , the Gilded Age value investor called both the "Witch of Wall Street" and the "Queen of Wall Street," disappears into history behind Benjamin Graham and his protege Warren Buffett. The problem I faced is that no one was seeing my bios, so I decided to make short videos or reels in hopes of increasing my reach. Creating the technical infrastructure for the reels on top of my existing system was fun and relatively straightforward. Each reel consists of a series of "beats," and Remotion turns those beats into a vertical reel, complete with on-screen text and royalty-free images & attributions pulled from Wikimedia, Flickr, or Library of Congress. For content, the beat generator relies on the knowledge base of validated facts that my system creates f

Anthropic’s Claude Sonnet 5 brings stronger agentic capabilities, lower pricing, and improved safety, positioning the model as a cheaper alternative to Opus, GPT-5.5, and Gemini Pro.

Anthropic's Claude Science is a workbench that gives scientists one environment to do computational research, saving them from the need to bounce between databases, pipelines, and tools.

A CFO will not act on a number an LLM eyeballed. They will not act on a number the model "estimated" by reasoning over a usage dump. And they should not — because the moment a language model emits a dollar figure it computed itself, that figure is a guess wearing the costume of a fact. This is the design constraint behind databricks-cost-leak-hunter , the pilot skill of the databricks-pack v2 rebuild shipped in the claude-code-plugins marketplace ( PR #906 ). Given a live, authenticated Databricks workspace, it surfaces real cost leaks across four named categories, ranks them by monthly dollar impact, and emits a report a finance reader can act on. The marketplace validator graded it B (88/100, zero errors). The SKILL.md is 329 lines. The single most important thing in it is a rule the model is structurally prevented from breaking: the LLM never does the dollar arithmetic. Why not just let the agent read the bill and summarize it? Because that is exactly how you ship a confidently wrong cost report. Hand a model a few thousand rows of system.billing.usage and ask it for the top cost leaks, and it will give you a fluent answer. It will add DBUs. It will multiply by a price it half-remembers. It will round. Every one of those steps is a place the model can be plausibly, invisibly wrong — and the output reads identically whether the math is right or hallucinated. The failure mode of an LLM doing FinOps is not a crash. It is a clean, well-formatted, wrong number. The fix is architectural, not prompt-engineering. The model is allowed to decide what to look for and how to explain it . It is never allowed to be the calculator. The dollar primitive: confirmed, never estimated Every confirmed figure comes from the customer's own billing tables — system.billing.usage joined to system.billing.list_prices . Not a model estimate. Not a public price list. The number Databricks actually billed. That join is defined once, as a priced CTE, and reused by every category query. Usage i

There is a sentence my coding agent used to say that I now read as a warning light. You are completely right. For months I took it as a compliment. The machine agreed with me, so I figured I was onto something. I would describe a plan, watch the agent call it a strong plan, and go build it. If you work with an AI agent every day, you have heard your own version of this. Smart call. Solid approach. That makes a lot of sense. Each one is the machine nodding along while you talk. It feels good. That is the problem. What took me too long to admit An agent that agrees with everything I say stops being a thinking partner. It turns into something that flatters me into shipping my first idea. My first idea is rarely my best idea. Nobody's is. The whole point of a second mind in the room is that it pushes back when the first mind is about to walk into a wall. A yes-machine removes the one thing that made a second mind worth having. This has a name Sycophancy. These models are trained to be agreeable, because agreeable scores well in the feedback that shapes them. OpenAI said so out loud in 2025 when they pulled back a version of their model for being, in their words, overly flattering. They were pointing straight at the default behaviour. So your agent is doing exactly what it was tuned to do when it tells you that you are right. No malfunction involved. One opinion most builders have not made peace with Your agent's confident wrong answer costs more than a useless one. A useless answer wastes a minute. You see it is useless and move on. A confident wrong answer wastes a week, because you trusted it, built on it, and found out only when it broke in front of someone who mattered. Occasional wrongness is survivable. Everything is wrong sometimes. What actually bites is being wrong while sounding certain, and agreeable, and exactly like what you wanted to hear. How to tell if your agent is a yes-machine You can test it in a minute. Tell it a bad idea on purpose. Propose somethi

There is a habit that wastes more time than anything else when using Claude. Save this :) Writing the same instructions over and over again. Every session, you re-explain your role. You re-describe your writing style. You re-state your formatting preferences. You re-paste your company context. You re-specify what you want the output to look like. Then you do it again tomorrow. And the day after that. And the day after that. Over a month, you waste hours on instructions you have already written. Not new thinking. Not new requests. Just the same setup, repeated endlessly. Claude Projects and Skills fix this completely. Projects let you save context once and have it applied to every conversation automatically. Skills let you save entire workflows as reusable commands that you can trigger with a single sentence. Together, they turn Claude from "a tool you use from scratch every time" into "a system that already knows everything and just needs your specific request." Here is how to set them up from zero. What Are Claude Projects A Claude Project is a container for conversations that share the same context. When you create a Project, you upload knowledge files and write a system prompt. Every conversation inside that Project automatically has access to those files and follows those instructions. No re-explaining. No re-pasting. No re-describing. The context is always there. Example: you create a Project called "Content Marketing." You upload your brand guidelines, your editorial calendar, your top-performing articles, and your audience personas. You write a system prompt: "You are my content strategist. You know our brand voice, our audience, and our content strategy. Every piece of content should match our guidelines and target our defined personas." Now every conversation in that Project - brainstorming headlines, drafting articles, analyzing competitors - starts with full context. Claude already knows your voice, your audience, and your standards. One setup. Unlimited

Your AI coding agent writes something that looks right. It compiles in your head. Then you notice it called user.getProfileById() — a method that doesn't exist anywhere in your codebase. You didn't ask it to make that up. It invented it confidently, in the middle of otherwise-fine code. And that's the worst kind of wrong: not obviously broken, just quietly incorrect in a way you have to catch. If you've run Claude Code, Cursor, or any agent on a real repo, you know this one. Here's why it happens — and why the obvious fix doesn't work. The fix everyone tries first (and why it fails) You reword the prompt. You add "Don't make up functions." It behaves… for one file. Then it does it again. So you add "Only use methods that exist in the provided code." Better for a bit. Then two more sentences — and now your prompt is fifteen rules long and it still invents a method the moment the task gets complex. Here's the part nobody tells you: rewording treats a structural problem as a vocabulary problem. A prompt isn't a contract the model reads once and obeys. It's something the model has to hold in working memory while it reasons about your actual task. A flat list of fifteen rules is unholdable. As the work gets harder, the model spends its attention on the code and quietly drops whichever rule wasn't front-of-mind. "Don't invent methods" is usually rule #11. Under load, it falls out. You can't out-word that. A sixteenth rule just gives it one more thing to drop. The actual cause: shape, not wording The agent invents a method because nothing in the prompt's structure requires it to check. You told it what not to do. You never changed what it actually does, step by step. So stop forbidding the bad thing. Remove the opportunity for it. Instead of a rule it has to remember, make grounding a required step it has to perform. Before — a pile of rules:You are an expert engineer. Write clean code. Follow our conventions. Don't make up functions. Only use methods that exist. Handle er

Last night I was deep in a build session with an AI assistant. We picked it back up tonight. At some point I mentioned it had been a day and a half since we last spoke — and the model had no idea. None. As far as it knew, it was still the previous session. The gap was invisible to it. That tiny moment is one of the most underrated problems in AI systems right now. So let's talk about it. The model doesn't know what time it is An LLM gets a rough sense of "now" at the start of a conversation — a single timestamp, handed to it once. That's why it can greet you with "good morning." But that stamp is frozen. It doesn't update as the conversation runs, and it definitely doesn't travel into the next conversation. Each session starts cold. On its own, that's a curiosity. It becomes a real problem the moment the model reasons over retrieved context — search results, documents, database rows, another agent's output. Staleness is invisible Here's the dangerous part. When a model reads a retrieved document, that document usually carries no trustworthy signal about when it was true . So the model treats it as present-tense. It produces a confident answer from six-month-old data with nothing flagging that the data is old. A few places this bites: Pricing — quoting a number that changed last quarter. Availability — "in stock" from a cached page. Compliance — citing a policy that was superseded. People — stating someone's job title from two years ago. For a human reader, a slightly stale search result is fine — you see the date and judge for yourself. For an LLM, the staleness is silent. The wrong answer looks exactly like a right one. Why "just add a clock" doesn't fix it The instinct is: give the model the current time. But knowing it's 9 PM doesn't help if the document you're citing went stale in 2023 and nothing told you. The missing piece isn't the model's clock — it's the context's freshness . Two different things: What time is it now? — easy, a now() call solves it. How old

TL;DR — Claude Code sends its requests wherever one environment variable points. Aim that at a small local translator and it runs on the Kiro plan you already pay for. Full setup below, plus the two snags worth knowing about. Claude Code and Kiro have something funny in common: underneath, they're powered by the same Claude models. Same brain. They just grew up speaking different dialects, so out of the box they can't hold a conversation. I noticed this right as I was about to start a second subscription for Claude Code. My Kiro plan was already renewing every month, already serving the exact models Claude Code wanted to charge me for again. Paying twice to talk to the same thing felt absurd. So instead of buying a second seat, I hired an interpreter. One small program that sits between them, listens to Claude Code, and relays everything to Kiro in a dialect it understands. Here's how to set it up, and what I learned doing it. Why they can't just talk Claude Code is more open-minded than people assume. It doesn't hard-code where it sends requests. It reads one environment variable, ANTHROPIC_BASE_URL , and ships everything to that address. Normally that's the official endpoint, but it'll happily send its requests anywhere you tell it to. That's the opening. Point it somewhere local and the whole thing becomes possible. Meet the interpreter The catch is that Claude Code and Kiro phrase things differently. You can't just redirect one at the other and expect them to understand each other. You need a translator fluent in both. That's kiro-gateway-next : a tiny proxy that runs on your own machine. A request arrives phrased one way and leaves phrased another: Claude Code (phrases it for Anthropic) ──▶ kiro-gateway (rephrases it for Kiro) ──▶ your Kiro account Claude Code gets a reply in the format it expects. Kiro receives a request it recognizes. The interpreter does the rephrasing in the middle, and the conversation just flows. Setting it up, step by step Six steps. Abo

For the last 3 months I recorded every session I had with Claude Code. Not screenshots, not memory. Every prompt I typed and everything it did, saved to a small database I own. I did it because I kept losing my own work. I would finish a week, someone would ask what I shipped, and I genuinely could not remember. The work was real. It just lived in terminal scrollback I would never scroll through again. So I set up a chain of small agents to remember it for me. Every night, while I sleep, one agent reads that day's raw sessions and writes a single clear note: what I built, the decisions I made, what is still open. Plain language, the way I would write it in a journal, not a wall of logs. Once a week, a second agent reads all seven daily notes and updates a profile of me: the projects I am moving, the skills I have actually used, the things I learned. After a few months this turned into a more honest picture of my work than my resume. Then a third agent reads all of that and drafts posts for LinkedIn and X about what I actually worked on that week. Building in public, without me having to remember or sit down and write. The part I like most: none of it runs on my machine. It is all scheduled cloud routines. My laptop can be off. I wake up and the notes, the profile, and the draft posts are already waiting. I have started open-sourcing this as Pulse. The capture and the nightly daily-note agent are out now. You point it at your own database and your own notes repo, and it writes your day for you, in plain English, in files you own. The weekly profile agent and the post-writer are the pieces I am extracting next. It is early and rough in places. The honest caveat: the writing is only as good as the model behind it, and a quiet day still makes a quiet note. But after 3 months, I no longer guess what I did. I just open the vault. The graph at the top is 3 months of my own notes, each day linked to the projects it touched. Repo: https://github.com/muhammademanaftab/pulse

The problem: agents forget your project every session If you pair with a coding agent, you have lived this: a new session starts and the context is gone. The agent re-discovers your auth flow, re-guesses why a decision was made, re-reads the same files to rebuild a mental model you already explained yesterday. Project knowledge — the why behind your systems, the runbooks, the "don't touch this, here's the reason" — lives scattered across wikis, code comments, and people's heads. None of it travels with the code, and none of it survives a fresh context window. CLAUDE.md helps, but it's for standing instructions , and it gets loaded wholesale into every prompt. Auto-memory captures what an agent picked up, but it's implicit, per-agent, and not reviewed. A wiki is for humans and needs exporting. There's a gap: curated team knowledge that's structured, versioned with the code, and readable by any agent or person. What OKF is Open Knowledge Format is an open, vendor-neutral format (announced by the Google Cloud Data Cloud team in June 2026, Apache-2.0) that represents knowledge as a directory of markdown files with YAML frontmatter . That's the whole idea. No schema registry, no runtime, no SDK. If you can cat a file you can read it; if you can git clone a repo you can ship it. A bundle looks like this: .okf/ ├── index.md # progressive disclosure (root carries okf_version) ├── log.md # ISO-dated change history, newest first ├── services/auth-api.md # one concept = one file; path is its ID ├── datasets/orders-db.md ├── decisions/use-okf.md ├── runbooks/payment-failures.md └── metrics/checkout-conversion.md Each concept needs exactly one thing to be conformant: YAML frontmatter with a non-empty type . Everything else is optional. --- type : Service title : " Auth API" description : " Issues and verifies short-lived access tokens." resource : https://github.com/acme/auth tags : [ auth , platform ] timestamp : 2026-06-14T10:00:00Z --- # Endpoints | Method | Path | Descriptio

One morning I pasted four principles into my CLAUDE.md , the global instruction file Claude Code reads at the start of every session. "Think before you code", "simplicity first", that kind of maxim you see fly by on X, credited to Andrej Karpathy. I felt clever for about a day. Then I watched Claude read the file, nod, and carry on exactly as before. A CLAUDE.md is a suggestion box. The model nods, then does whatever it wants. If I wanted it to code my way, writing it down wasn't going to cut it. I had to enforce it. What follows is what that frustration turned into: a config in four layers, reinstallable in one command, and a discovery that runs through everything else. The only rigor that counts is the one a model can't grant itself. Four layers, and only one really changes the behavior My config has four floors, from softest to hardest. The brain is CLAUDE.md : how I work, not the docs for my code. The rule that sums it up lives inside it: "what not to add: anything Claude rediscovers by reading the code." It holds my design principles, my stance on orchestrating subagents (I size up, I delegate, I verify: "I stay the brain, they're the hands"), and one line that becomes the thread running through the whole thing. The references : a go-best-practices.md file the brain points to in plain text whenever Go is involved. The skills : ten of them. A skill is a folder with a playbook that Claude loads on demand for a specific job: review code, write an article, distill a book. Mine are packaged as a marketplace, in a public GitHub repo , with a changelog and a version number. That's the real differentiator: versioned tooling, not just rules scribbled in a file. The guardrails , finally. And this is the only layer that reliably changes behavior. The first three, the model can read and ignore. The fourth, it can't. The four config layers, from softest (the model can ignore) to hardest (the model is bound by the guardrail) Brain CLAUDE.md: how I work References go-best-pra

If you have built an estimate in the AWS Pricing Calculator by hand, you know the drill. Open calculator.aws, search a service, click in, stare at twenty fields half of which you do not need, guess at the ones the form does not explain, pick a region, repeat for every service. Then redo the whole thing next week when the customer asks what it looks like in Frankfurt. For presales that is not a small annoyance. It is the gap between giving a number on the call and saying "let me get back to you." I wired the AWS Pricing Calculator MCP into Claude, and the first real estimate I built took one sentence. What it is An MCP server - an AWS Samples project - that exposes the Pricing Calculator as tools an agent can call. You describe the workload, the agent assembles the estimate, the server saves it to the real calculator, and you get a shareable calculator.aws URL back. Same link you would have built by hand, minus the form. Three things make it usable in front of a customer: No AWS credentials. It hits the public, unauthenticated calculator.aws endpoints. You are not pointing it at an account or assuming a role. There is no blast radius. Live definitions. It pulls the calculator manifest at runtime - about 436 services - so it is current, not a snapshot from six months ago. Real, editable estimates. The URL it returns opens in the actual calculator. Tweak it, send it, whatever. The agent just did the boring part. It runs over stdio for local clients like Claude Desktop, Kiro, and Cursor, or over HTTP ( MCP_TRANSPORT=http ) if you want it hosted. It also handles the aws-iso and aws-eusc partitions, which matters for sovereign and regulated work. Context is the whole job The honest part: it is amazing when you feed it the right context . Ask for "an estimate for a web app" and you get back a web app someone else imagined. The calculator never knew your traffic - you did. The MCP does not change that. What it changes is the translation. Once you know the shape - two m5.lar

Everyone hits the same wall with Claude Code. You add a rule to CLAUDE.md . It works. You add ten more. They mostly work. You add forty more — and now Claude is cheerfully ignoring the rule you care about most, the one that's been sitting there since day one. So you make it LOUDER , in caps, with three exclamation points. It still gets skipped. The instinct is to write more. The fix is almost always to write less . Here's why, and what to do instead. Instruction-following has a budget, and you're overdrawn This is the part most CLAUDE.md guides skip. Frontier models reliably follow on the order of 150–200 instructions at once — and adherence to any single rule drops as you stack more on top of it. It isn't a cliff; it's a slow tax. Every line you add makes every other line a little less likely to be honored. Now subtract what you don't control: Claude Code's own system prompt already spends a chunk of that budget before your file is even read. So the working budget for your project rules is smaller than the headline number — and a sprawling 300-line CLAUDE.md isn't 300 rules followed, it's maybe the first 150 followed well and the rest treated as ambience. The mental model that fixes everything downstream: CLAUDE.md is a budget, not a wishlist. You are not writing documentation. You are spending a scarce attention allowance, and every line competes with every other line. The test for every line: would you bet $5 it's followed? Go through your file line by line and ask one question of each rule: would I bet money this fires every time it's relevant? Three outcomes: Yes, and it's load-bearing — keep it. This is what the budget is for. Nice to have, but I wouldn't bet on it — cut it, or move it to a referenced file (below). It's diluting the rules you would bet on. It absolutely must happen every time — then it doesn't belong in CLAUDE.md at all. Make it a hook. That third category is the one people get wrong, so let's be concrete about it. Advisory vs. deterministic:

As Anthropic tightens restrictions on access to Claude in China, users keep finding new workarounds, from proxy services to fake identities sourced on Telegram.

I run Claude Code most of the day. The thing that kept biting me wasn't the model getting dumber. It was the model forgetting what we'd already settled, then confidently redoing it wrong. You've probably hit it. You write a CLAUDE.md , you keep notes, you tell it "we decided X." A few prompts later it relitigates X, or quietly breaks something it fixed an hour ago. Bigger context windows didn't fix it for me either. A 1M window just means more room for stale instructions to rot in. Here's the reframe that actually held: stop treating the model as the place the state lives. The model is a worker, not a filing cabinet A context window is working memory, not a record. It's lossy, it drifts, and every new turn re-derives the world from whatever's in front of it. If "what's done and what's half-broken" only exists in that window, you're trusting the most forgetful part of the system to remember the most important thing. So I moved the state out of the model and into the work. Two pieces did most of it: A frozen spec the agent re-reads. Not a chat message it might compress away. An actual file that says what we're building and what's already decided. When it starts drifting, the spec is the source of truth, not its memory of the conversation. A checklist it can only tick after something is verified. [ ] becomes [x] when a test passes or I've confirmed the change, never because the model "thinks" it's done. The checklist carries the progress. The model just moves it forward one verified step at a time. The difference is subtle but it's the whole game. Before, the work was a side effect of the conversation. After, the conversation is a side effect of the work. The agent can lose the whole thread and reload from the spec plus the checklist and basically pick up where it left off. A number that surprised me When I actually measured my own sessions, almost none of my tokens were fresh input. The bulk was cache reads and re-reading instructions that hadn't changed. So the "cont

7 daily crons, 2 starvation incidents that triggered the rewrite Health checks before work, not after, catch silent failures Queue-low alarm fires at 5 items, not at zero A cron is ignorable for 3 weeks only when failures are loud I run 7 GitHub Actions crons every day, and for two months I never looked at them. Then a content queue starved silently and I posted nothing for 4 days before noticing. Here is what I changed so a cron can stay green and be ignorable for 3 weeks straight. The Two Incidents That Forced The Rewrite The first starvation happened on a Tuesday. My image generation cron pulled prompts from a queue, made the assets, and pushed them to a publish queue. The image API returned a 429 (rate limited) and the job exited cleanly with a green checkmark. GitHub Actions reported success. The workflow logs said "0 prompts processed" in a line I never read. For 4 days the publish queue drained and nothing refilled it. I found out because a follower asked why I went quiet. The second incident was sneakier. A cron that calls an external API hit an auth token that had expired. The script caught the error, logged it, and returned exit code 0 because I had wrapped the whole thing in a try/except that swallowed everything. Green check, no work done. This one ran for 6 days before I caught it during an unrelated debug session. Both failures shared one root cause: a green checkmark in GitHub Actions means the process exited zero, not that the work happened. Those are completely different claims. A cron that catches its own errors and exits clean is lying to you in the most polite way possible. After the second incident I sat down and wrote out what I actually wanted. I wanted to never look at these workflows unless something was wrong. I wanted "wrong" to be loud. And I wanted the loudness to arrive before the damage, not after. That meant three changes. First, the exit code had to reflect real work, so swallowed exceptions had to re-raise or set a failure flag. Sec

The problem Just saying "hi" to Claude Code costs ~31,000 tokens . I was paying $500+/month in API costs and had no idea where the tokens were going. So I built tokenwise — a free CLI that shows exactly where your AI coding agent wastes tokens. What it does tokenwise audit — Scan your instruction files It scans your CLAUDE.md, AGENTS.md, and rules files, then shows: How many tokens each file costs per message Boilerplate the AI already knows ("Always write clean code") ALL-CAPS emphasis that doesn't help (NEVER, ALWAYS, MUST) Duplicate sections Unscoped rules that load when they shouldn't tokenwise scan — Analyze your sessions It reads your latest session logs and shows: Token breakdown by component (system prompt, history, tool output) Cache hit rate Top 3 "token hogs" with actionable tips Monthly cost projection The key insight Most people try to compress context (which makes the AI dumber). tokenwise measures first, then applies safe fixes. You can't optimize what you can't measure. Quick start npx @davizin713/tokenwise audit npx @davizin713/tokenwise scan Zero API calls. Zero LLM inference. 100% local. Free forever. Works with 11 agents Claude Code, OpenCode, Cursor, Aider, Cline, Codex CLI, Goose, Continue.dev, Windsurf, Augment, and Kilocode. Links GitHub: github.com/davi713albano-coder/tokenwise npm: npmjs.com/package/@davizin713/tokenwise Built with TypeScript / Node.js js-tiktoken for token counting sql.js for reading OpenCode sessions MIT licensed If you use Claude Code or any AI coding agent, try it and let me know what you think! ⭐

Despite ChatGPT's commanding market lead, consumers who pay for AI have been increasingly choosing Anthropic's Claude, data shows.

You use Claude Code, or ChatGPT, or both, every day. Quick question: how many messages did you send last month? Which model ate most of your budget? How much did prompt caching actually save you? You don't know. I didn't either. That's a weird gap. We instrument everything else — git activity, deploy frequency, test coverage — but the tool we now spend the most hours inside is a black box. The vendor dashboard, if it exists, is a billing page, not a mirror. So I built four tiny tools to fix that for myself. They all run 100% locally . No accounts, no API keys, no telemetry, no network calls. They read files that are already on your disk and print something you can look at. All four are open source on github.com/greymoth-jp — and because that's a real claim, the only thing I'll ask is that you grep the source yourself before you trust me. Here's the privacy point up front, because it's the whole design: these read your data, but your data never leaves your machine. That's not a feature I'm bolting on for a marketing line. It's the reason the tools are small enough to audit in one sitting. The one number that changed how I work Before the tools, here's what I assumed: my Claude Code bill is dominated by the prompts I write, so to spend less I should write tighter prompts. Compress the context. Trim the system message. The usual advice. I ran the numbers on my own ~/.claude transcripts and got this: component share of cost cacheRead 72% cacheWrite ~19% output the rest input ~0.3% Input — the thing everyone tells you to compress — was 0.3% of my spend. Compressing my prompts to save money would've been optimizing the rounding error. Worse: compressing a static prompt changes its bytes, which busts the prefix cache, which can make the bill go up . The real cost center was cache reads: long sessions dragging a fat context forward, turn after turn. That points at completely different levers — cache hygiene (milestone /compact , /clear before the context balloons, keeping C