Align Fly agents with Project-owned MCP connections

Co-authored-by: Annedaynl <info@anneday.nl>
Signed-off-by: Annedaynl <info@anneday.nl>

Author: Annedaynl

Dockerfile.fly-agent

@@ -1,6 +1,5 @@
 # syntax=docker/dockerfile:1.7
-# Buzz cloud-agent image: the pinned Sprig runtime plus a pinned bridge for
-# remote Streamable HTTP/SSE MCP servers.
+# Buzz cloud-agent image: the pinned Sprig runtime used by isolated Fly agents.
 FROM rust:1.95-alpine3.22@sha256:064dfc925d68d1a63f4fd2871bd7dc6e6ea56692989a487185855d62885d90aa AS builder
 
 RUN apk add --no-cache \
@@ -20,12 +19,7 @@ RUN cargo build --locked --profile sprig -p sprig \
 
 FROM alpine:3.22@sha256:14358309a308569c32bdc37e2e0e9694be33a9d99e68afb0f5ff33cc1f695dce
 
-# mcp-remote is pinned: cloud agents must not execute the newest npm package
-# merely because a Machine restarted. Update this version through the normal
-# image review and rollout path.
-RUN apk add --no-cache bash ca-certificates curl git nodejs npm su-exec \
-    && npm install --global --ignore-scripts mcp-remote@0.1.38 \
-    && npm cache clean --force \
+RUN apk add --no-cache bash ca-certificates curl git su-exec \
     && adduser -D -h /home/agent agent \
     && install -d -o agent -g agent /workspace /home/agent \
     && git config --system gpg.format x509 \
@@ -43,7 +37,6 @@ RUN for name in \
     done
 
 ENV HOME=/home/agent \
-    MCP_REMOTE_CONFIG_DIR=/home/agent/.mcp-auth \
     PATH=/usr/local/bin:/usr/local/sbin:/usr/sbin:/usr/bin:/sbin:/bin
 WORKDIR /home/agent
 ENTRYPOINT ["/usr/local/bin/fly-agent-entrypoint"]

crates/buzz-acp/README.md

@@ -111,7 +111,6 @@ All configuration is via environment variables (or CLI flags — every env var h
 | `BUZZ_ACP_AGENT_COMMAND` | no | `goose` | Agent binary to spawn. |
 | `BUZZ_ACP_AGENT_ARGS` | no | `acp` | Agent arguments (comma-separated). |
 | `BUZZ_ACP_MCP_COMMAND` | no | `""` (empty) | Path to an optional MCP server binary to provide to the agent subprocess. |
-| `BUZZ_ACP_MCP_SERVERS` | no | — | JSON array of additional stdio MCP servers. Supports `name`, `command`, `args`, literal `env`, `inherit_env` names resolved from the harness environment, and optional exact `allowed_tools`. Maximum 16 total including `BUZZ_ACP_MCP_COMMAND`. |
 | `BUZZ_ACP_IDLE_TIMEOUT` | no | `620` | Idle timeout: max seconds of silence before cancelling a turn. Resets on any agent stdout activity. |
 | `BUZZ_ACP_MAX_TURN_DURATION` | no | `7200` | Absolute wall-clock cap per turn (safety valve). |
 | `BUZZ_API_TOKEN` | no | — | API token (required if relay enforces token auth). |
@@ -120,42 +119,6 @@ All configuration is via environment variables (or CLI flags — every env var h
 
 **Legacy env vars:** `BUZZ_ACP_PRIVATE_KEY`, `BUZZ_ACP_API_TOKEN`, and `BUZZ_ACP_TURN_TIMEOUT` (replaced by `BUZZ_ACP_IDLE_TIMEOUT`) are still accepted as fallbacks.
 
-### Additional MCP servers
-
-`BUZZ_ACP_MCP_SERVERS` lets one agent attach multiple account-scoped MCP
-servers without rebuilding `buzz-acp`. Keep credential values in the process
-environment and name them through `inherit_env`; the harness resolves those
-values only when it starts the corresponding child process.
-
-```bash
-export CRM_AUTH_HEADER='Bearer account-specific-token'
-export BUZZ_ACP_MCP_SERVERS='[
-  {
-    "name": "crm",
-    "command": "mcp-remote",
-    "args": [
-      "https://crm.example/mcp",
-      "--header", "Authorization:${CRM_AUTH_HEADER}",
-      "--transport", "http-only"
-    ],
-    "inherit_env": ["CRM_AUTH_HEADER"],
-    "allowed_tools": ["search_contacts", "create_note"]
-  },
-  {
-    "name": "local_reporting",
-    "command": "/opt/mcp/reporting-server",
-    "args": ["--read-only"]
-  }
-]'
-```
-
-The server command must already exist in the agent image or host. Remote HTTP
-connections therefore use a pinned proxy such as `mcp-remote` only when that
-proxy is part of the trusted image; avoid pulling an unpinned package at agent
-startup. When `allowed_tools` is non-empty, Buzz Agent exposes only those exact
-bare tool names from that server. Omitting it preserves the ACP default of
-exposing every server tool.
-
 ### Parallel Agents & Heartbeat
 
 | Flag | Env Var | Default | Description |

crates/buzz-acp/src/acp.rs

@@ -30,10 +30,6 @@ pub struct McpServer {
     pub command: String,
     pub args: Vec<String>,
     pub env: Vec<EnvVar>,
-    /// Buzz extension: exact bare tool names this server may expose. Empty
-    /// preserves the ACP default of exposing every server tool.
-    #[serde(rename = "allowedTools", skip_serializing_if = "Vec::is_empty")]
-    pub allowed_tools: Vec<String>,
 }
 
 /// A single environment variable for an MCP server.
@@ -2446,7 +2442,6 @@ mod tests {
                     value: "nsec1abc".into(),
                 },
             ],
-            allowed_tools: vec![],
         };
         let serialized = serde_json::to_value(&server).unwrap();
         assert_eq!(serialized["name"].as_str(), Some("test-mcp"));