Landing page of the **official specification** of the **Agent Client Protocol (ACP)** (`agentclientprotocol.com/get-started/introduction`), accessed on **August 2, 2026**. This is not a dated article but a **living artifact**: the fiche is dated by its observation, not by a publication date. **One-sentence mission statement**: *« The Agent Client Protocol (ACP) standardizes communication between code editors/IDEs and coding agents and is suitable for both local and remote scenarios. »* **The stated problem** fits in three lines: coding agents and editors are **tightly coupled** and *« interoperability isn't the default »* — every editor must build a custom integration per agent, every agent must implement editor-specific APIs. Three named consequences: **integration overhead** (every agent-editor pair requires custom work), **limited compatibility** (an agent reaches only a subset of editors), **developer lock-in** (*« choosing an agent often means accepting their available interfaces »*). **The solution is explicitly modeled on LSP** — *« similar to how the Language Server Protocol (LSP) standardized language server integration »* — with the mutual benefit: an agent that speaks ACP works with **any** compatible editor, an editor that supports ACP gains access to the **entire** ACP agent ecosystem. **Two deployment modes, and this is the most underrated point**: **local** agents run as a subprocess of the editor over **JSON-RPC on stdio**, but **remote** agents are planned over **HTTP or WebSocket** — support declared *« work in progress »*, with ongoing collaboration with agentic platforms. **Technical lineage with MCP, stronger than mere complementarity**: ACP *« re-uses the JSON representations used in MCP where possible »*, adding types specific to agentic coding UX needs (**diff** display is the example given); the default format for readable text is **Markdown**, chosen so the editor is not required to render HTML. **Two governance and versioning observations** drawn from the page itself, not from surrounding discourse: the navigation exposes **v1 (Latest)** and **v2 (Draft)** — and **not an "ACP 1.2"** —, and the navigation bar links **Zed Industries *and* JetBrains** side by side, alongside an **ACP Registry**, **RFDs**, a **Community** section, **Publications**, **Updates**, and a **Brand** page. Official libraries announced: **Kotlin, Java, Python, Rust, TypeScript**, plus a community track.
#Agent Client Protocol#ACP#open protocol
**Projet Agent Client Protocol** — spécification collective · sans signature individuelle sur cette page. La barre de navigation du site lie deux organisations au même niveau : **Zed Industries** (à l'origine du protocole) et **JetBrains**. La présence d'une section **RFDs** (*requests for discussion*) · d'une page **Community** et d'un **ACP Registry** indique une structure de gouvernance ouverte plutôt qu'une documentation produit.
Tech-watch note by **Didier Girard** dated **August 2, 2026**, prompted by a colleague's question ("what is ACP?") to address a problem that is not terminological but **documentary**. **Three protocols compete for the acronym**, with no technical overlap whatsoever: **Agent Client Protocol** (client ↔ agent — Zed, August 2025, JSON-RPC 2.0 over stdio, Apache-2.0, "what LSP did for languages"), **Agentic Commerce Protocol** (agent ↔ merchant — OpenAI + Stripe, Sept. 29, 2025, competing with Google's **UCP** of Jan. 11, 2026 backed by **AP2**), and **Agent Communication Protocol** (agent ↔ agent — IBM Research / BeeAI, marginal but polluting searches). **The core of the note is not the disentangling but its observed failure**: the author searches "ACP" in their tech-watch knowledge base and gets **twelve results, all about the commerce protocol, zero about Zed's** — *"our watch agents had indexed the acronym without disambiguating it"*. Hence a knowledge-engineering rule: ***"a bare acronym is never indexed"*** — the entity is "Agent Client Protocol", "ACP" is **only an alias**, carried by three distinct entities. A structuring clarification follows (**MCP connects an agent to its tools, ACP connects a client to an agent; the two stack**), then the textbook case: **Buzz**, published by **Block** on July 21, 2026 under Apache-2.0 — a self-hostable workspace built on **Nostr**, where every human or agent participant is a **key pair** and every message, workflow step, or git push is a **signed event** in an append-only log. An entirely protocol-based architecture (`buzz-acp` an ACP harness over stdio, `buzz-agent` an ACP agent calling an LLM, `buzz-dev-mcp` an MCP shell + editing server), hence agent agnosticism: **Goose, Claude Code, and Codex** plug in through the same harness, and **Hermes** (Nous Research) connected to it without Block writing a single line — *"N+M instead of N×M, running in production"*. The note closes on the question of the **Claude subscription** versus third-party agents, with a five-stage 2026 timeline and a **design rule** that holds beyond this case: the line is not legal but **architectural** — ***"who is consuming, and on whose behalf"*** (an `owner-only` agent consumes your subscription on your behalf; an `anyone` agent in a shared channel routes your colleagues' requests through your account). **Verification carried out on this corpus**: the thesis holds, and more starkly than the note claims — not only is "Agent Client Protocol" **completely absent**, but the bare acronym `ACP` **is already typed as an entity** in two fiches, and the KB page `Agentic-Commerce-Protocol` **already attributes the protocol to Google** when it belongs to OpenAI + Stripe. The collision described is not a future risk: it has **already produced an attribution error** in the graph.
**Didier Girard** — auteur de la note. Écrit ici depuis la position de **praticien de la veille outillée** : le déclencheur est une question de collègue · le matériau principal est le comportement observé de sa propre base de connaissances · et la conclusion est une **règle de curation** adoptée en interne. Le texte alterne donc deux voix — l'explicateur de protocoles et l'ingénieur de la connaissance qui constate un défaut chez lui et en tire une norme.
Reference page published on **eventuallycoding.com** on **July 28, 2026** by **Hugo Lassiège** (Lyon, developer turned entrepreneur, author of Bloggrify, Hakanai, and Writizzy). The author announces it as such: *"This will be more of a reference page than an article,"* intended for his own resources page. **Subject**: an exhaustive, tooled description of a **solo software factory** where *"the code produced is now nearly 100% generated,"* across several polyglot monorepos (Nuxt, Kotlin, JS — Hakanai, Writizzy, Bloggrify) in **continuous deployment to production**. **Distinction stated upfront**: this is not **vibe coding** in Karpathy's sense (experimentation, letting oneself be carried along) but **context engineering** — *"giving all the necessary context, at the right time, so that the software matches an intention and is systematically controlled,"* with the sentence that grounds the responsibility: *"Even if I don't write the code, I am responsible for it and must keep control over it."* **The entire toolset answers three questions**, and this is the text's most reusable reading grid: *"What does the agent know?"* (context, memory, code graph) — *"What does it know how to do deterministically, without improvising?"* (skills, procedures) — *"What stops it when it gets it wrong?"* (hooks, architecture tests, quality gates). **Six layers detailed**: (1) **context** — root `CLAUDE.md` + topical `.claude/rules/*.md` conditionally loaded via `paths:` + `.agents/*.md` for non-technical matters (personas, positioning, tone); (2) **skills** — about thirty, existence criterion *"if I explain the same thing a third time"*; (3) **tools** — JetBrains IDE MCP, **GitNexus** (code graph: `impact(symbol)`, `detect_changes()`), Claude-mem, RTK filtering wrapper, Sentry, read-only database; (4) **executable guardrails** — harness hooks, **architecture tests**, pattern linting (**ast-grep** for architecture decisions, not just ESLint); (5) **factory** — blocking quality gate with `needs:` on the quality job, five test stages; (6) **product process** — numbered specs with a drafting skill **and a closure skill**, design in Claude Design, staged delivery behind feature flags, distinction between **feature flipping** (Unleash) and **gating** (customer contract). **The rule that sums it all up**: *"What matters must be executable. An instruction is followed 'most of the time'… A hook or a test is followed all the time."* **A rarity for the genre**: a "To improve" section that exposes four lived limitations — the **impossibility of measuring a rule's obsolescence** (*"I have no way of knowing whether an old rule has become obsolete"*), the **rabbit hole** created by a boyscout rule, the **lack of packaging** for skills across projects, and above all the admission of tension: *"I am becoming less and less useful during implementation phases,"* *"torn between the satisfaction of having an increasingly efficient factory and the risk of losing knowledge."*
#software factory#context engineering#vibe coding
**Hugo Lassiège** — développeur devenu entrepreneur · basé à **Lyon** · écrit du code depuis 2001 et tient **eventuallycoding.com** (le blog a porté le nom `hakanai.free.fr` avant de devenir *Eventuallycoding* en 2013). *Eventuallycoding* est le nom-parapluie qui regroupe ses projets · sa chaîne YouTube et ses blogs.
**Zed** blog post signed by **Franciska Dethlefsen** (head of growth and marketing), published on **May 14, 2026** — the day after Anthropic's announcement — to answer Zed users' questions. **Subject**: starting **June 15**, Anthropic **splits Claude subscription billing into two pools** — one for its **first-party tools** (chat, the official Claude Code CLI), the other for **third-party agent and SDK usage** (anything going through **ACP**, `claude -p`, or a third-party tool). Usage via ACP **then stops drawing from the Pro or Max limits** and switches to a monthly **"Agent SDK" credit**: **$20 for Pro, $100 for Max 5x, $200 for Max 20x**. Once the credit is exhausted, usage continues **at standard API pricing** if overage is enabled — otherwise requests stop until the next cycle. **The figure driving the article**: subscriptions had until then subsidized agentic usage by a factor of **≈15 to 30×** relative to API pricing, and the new credits are billed **at full API rates** — hence *« for anyone using agents heavily, this is a major cost increase »*. **Three options are proposed**, in an order that reveals Zed's position: (1) keep the subscription by running the **official `claude` CLI in a terminal inside Zed** rather than via ACP — *« when the official claude CLI runs in the terminal, it uses your subscription's limits, not the new credit »*; (2) use Zed's built-in agent with the provider of one's choice (Zed-hosted models, API keys, Copilot, local Ollama, DeepSeek); (3) plug in **any ACP agent** — OpenCode, Codex, Factory, Cursor —, several of which still offer rate-limited subscriptions that subsidize heavy usage. **The underlying thesis**, and the real reason for the post: *« ACP is an open protocol… so that your editor is never locked into one provider's pricing decisions »*, with the explicit anticipation that *« this kind of change won't be the last »*. **The post carries an addendum dated June 16, 2026** announcing that **the change is suspended**: ACP, `claude -p`, the Agent SDK, and third-party applications continue to work with subscriptions **as before**, no separate credit to claim, limits unchanged, Anthropic revising its plan with advance notice announced. **The artifact is thus self-contradicting**: its most important content — the reversal — postdates its own publication date by a month.
#Zed#Anthropic#Claude subscription
**Franciska Dethlefsen** — head of growth and marketing chez **Zed Industries**. Le rôle est déterminant pour lire le texte : ce n'est pas un billet d'ingénierie mais une **communication de crise produit** · écrite le lendemain d'une annonce d'un fournisseur dont Zed dépend · à destination d'utilisateurs inquiets. La signature growth/marketing explique la structure (problème → options → réassurance) et le fait que l'argument protocolaire arrive en conclusion plutôt qu'en tête.