Announcement from **Google** on **August 6, 2026**: Google joins as **Core Maintainer** the **Agent Plugins 1.0.0** specification, an open, *vendor-neutral* packaging format for distributing **Agent Skills** and **MCP servers** together. The specification was published by a **TSC** whose Core Maintainers come from **Amazon, Cursor, Microsoft, OpenAI, and Vercel**; Google joins them, represented by **Kevin Hou** (Senior Staff Engineer, Google DeepMind). The two packaged building blocks — Agent Skills and MCP — originate from **Anthropic**, which does not appear on this list of maintainers. **The diagnosis** fits in one sentence: *"The core problem isn't the components. It's the manifest."* A skill is portable, an MCP server is portable; the box they go in is not, and every client had to invent it for itself — hence the forks, the copies of identical components, and their drift. **The format** fits in one constraint: *"A plugin is a directory. That's the whole idea, and the restraint is the point."* A `plugin.json` with two useful lines (`$schema` and `name`), skills in `skills/` in the Agent Skills format, servers declared in `mcp.json` with an **explicit `type` on each entry** (stdio, Streamable HTTP, or the legacy HTTP+SSE) — no more transport guessed from the shape of the config object. The strength of the design lies in what the manifest **cannot** do: neither relocate components nor declare them inline, so there is no discovery path to configure and no precedence order to learn. Operational corollary: components **fail independently** — an `mcp.json` server that fails to start does not take down the plugin's skills, the client skips the entry, keeps going, and reports the failure. The accepted escape hatch is the **reverse-domain** directory (`com.example.client/`), an extension space owned entirely by one client (hooks, agents, commands) that other clients ignore: *"the portable core stays small because the non-portable parts have somewhere legitimate to go."* A section is dedicated to cases where the format is not warranted — *"Not every skill should be a Plugin"*: a single MCP server to a single client, `mcp.json` suffices; a single skill needs no plugin. What v1 explicitly excludes, under *future considerations*: **no installation mechanism, no distribution protocol, no permissions model, no sandboxing requirement, no trust or provenance verification, no UX**. All of this fits into an independently adoptable four-layer stack — **find** (Agentic Resource Discovery), **describe** (AI Catalog, which would register the `application/agent-plugins+json` type), **package** (Agent Plugins), **run** (MCP + Agent Skills). Two Google products already ship: **Agents CLI** and **Data Agent Kit** (BigQuery, Spanner, Cloud SQL).
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.