feat(agent): add Pi coding agent support to setup tooling

README.md

@@ -61,7 +61,7 @@ Configure Railway agent support for AI coding tools:
 railway setup agent -y
 ```
 
-This installs Railway skills and configures the Railway MCP server for detected tools such as Claude Code, Cursor, Codex, OpenCode, GitHub Copilot, and Factory Droid.
+This installs Railway skills and configures the Railway MCP server for detected tools such as Claude Code, Cursor, Codex, OpenCode, GitHub Copilot, Factory Droid, and Pi.
 
 Use the focused commands when you only need one part of the setup:
 

src/commands/mcp/install.rs

@@ -5,7 +5,7 @@ use std::path::{Path, PathBuf};
 
 const REMOTE_MCP_URL: &str = "https://mcp.railway.com";
 
-/// Install the Railway MCP server config into AI coding tools (Claude Code, Cursor, OpenAI Codex, OpenCode, GitHub Copilot, Factory Droid).
+/// Install the Railway MCP server config into AI coding tools (Claude Code, Cursor, OpenAI Codex, OpenCode, GitHub Copilot, Factory Droid, Pi).
 ///
 /// Merges a `railway` server entry into each tool's MCP config file. Without `--agent`, only configures detected tools (those with their config dir present).
 #[derive(Parser)]
@@ -96,7 +96,7 @@ pub(crate) async fn install_mcp(agent_filter: &[String], remote: bool) -> Result
 fn supports_mcp(slug: &str) -> bool {
     matches!(
         slug,
-        "claude-code" | "cursor" | "opencode" | "codex" | "copilot" | "factory-droid"
+        "claude-code" | "cursor" | "opencode" | "codex" | "copilot" | "factory-droid" | "pi"
     )
 }
 
@@ -108,6 +108,7 @@ fn config_path(slug: &str, home: &Path) -> PathBuf {
         "codex" => home.join(".codex").join("config.toml"),
         "copilot" => home.join(".copilot").join("mcp-config.json"),
         "factory-droid" => home.join(".factory").join("mcp.json"),
+        "pi" => home.join(".pi").join("agent").join("mcp.json"),
         // supports_mcp gates this; unreachable in practice.
         _ => home.join(".unsupported"),
     }
@@ -117,7 +118,7 @@ pub(crate) fn mcp_configured_for_slug(home: &Path, slug: &str, remote: bool) ->
     let path = config_path(slug, home);
 
     match slug {
-        "claude-code" | "cursor" | "copilot" | "factory-droid" => read_json_or_empty(&path)
+        "claude-code" | "cursor" | "copilot" | "factory-droid" | "pi" => read_json_or_empty(&path)
             .ok()
             .and_then(|root| root.pointer("/mcpServers/railway").cloned())
             .is_some_and(|entry| json_mcp_entry_matches(&entry, remote)),
@@ -232,6 +233,14 @@ fn install_for(slug: &str, path: &Path, remote: bool) -> Result<()> {
             };
             write_json_mcp_servers(path, entry)
         }
+        "pi" => {
+            let entry = if remote {
+                json!({ "url": REMOTE_MCP_URL })
+            } else {
+                json!({ "command": "railway", "args": ["mcp"] })
+            };
+            write_json_mcp_servers(path, entry)
+        }
         _ => bail!("Unsupported MCP target: {}", slug),
     }
 }
@@ -587,4 +596,24 @@ mod tests {
         );
         assert!(mcp_configured_for_slug(home.path(), "factory-droid", true));
     }
+
+    #[test]
+    fn writes_pi_remote_mcp() {
+        let home = tempfile::tempdir().unwrap();
+        let path = home.path().join(".pi").join("agent").join("mcp.json");
+        std::fs::create_dir_all(path.parent().unwrap()).unwrap();
+
+        install_for("pi", &path, true).unwrap();
+
+        let written = std::fs::read_to_string(&path).unwrap();
+        let root: JsonValue = serde_json::from_str(&written).unwrap();
+        let railway = root.pointer("/mcpServers/railway").unwrap();
+
+        assert_eq!(
+            railway.get("url").and_then(JsonValue::as_str),
+            Some("https://mcp.railway.com")
+        );
+        assert!(railway.get("type").is_none());
+        assert!(mcp_configured_for_slug(home.path(), "pi", true));
+    }
 }

src/commands/mcp/mod.rs

@@ -16,7 +16,7 @@ pub struct Args {
 
 #[derive(Parser)]
 enum Commands {
-    /// Install Railway's MCP server config into AI coding tools (Claude Code, Cursor, OpenCode, Codex)
+    /// Install Railway's MCP server config into AI coding tools (Claude Code, Cursor, OpenCode, Codex, Pi)
     Install(install::Args),
 }
 

src/commands/skills.rs

@@ -10,9 +10,9 @@ const TARBALL_URL: &str =
     "https://github.com/railwayapp/railway-skills/archive/refs/heads/main.tar.gz";
 const SKILLS_PATH_PREFIX: &str = "plugins/railway/skills/";
 
-/// Install Railway agent skills for AI coding tools (Claude Code, Cursor, Codex, OpenCode, GitHub Copilot, Factory Droid, and all tools that support .agents/skills)
+/// Install Railway agent skills for AI coding tools (Claude Code, Cursor, Codex, OpenCode, GitHub Copilot, Factory Droid, Pi, and all tools that support .agents/skills)
 ///
-/// Always installs to ~/.agents/skills. Additionally installs to any detected tool directories (e.g. ~/.claude/skills, ~/.cursor/skills). Use --agent to target specific tools instead of auto-detection.
+/// Always installs to ~/.agents/skills. Additionally installs to any detected tool directories (e.g. ~/.claude/skills, ~/.cursor/skills, ~/.pi/agent/skills). Use --agent to target specific tools instead of auto-detection.
 #[derive(Parser)]
 pub struct Args {
     #[clap(subcommand)]
@@ -25,9 +25,9 @@ pub struct Args {
 
 #[derive(Parser)]
 enum Commands {
-    /// Install Railway agent skills for AI coding tools (Claude Code, Cursor, Codex, OpenCode, GitHub Copilot, Factory Droid, and all tools that support .agents/skills)
+    /// Install Railway agent skills for AI coding tools (Claude Code, Cursor, Codex, OpenCode, GitHub Copilot, Factory Droid, Pi, and all tools that support .agents/skills)
     ///
-    /// Always installs to ~/.agents/skills. Additionally installs to any detected tool directories (e.g. ~/.claude/skills, ~/.cursor/skills). Use --agent to target specific tools instead of auto-detection.
+    /// Always installs to ~/.agents/skills. Additionally installs to any detected tool directories (e.g. ~/.claude/skills, ~/.cursor/skills, ~/.pi/agent/skills). Use --agent to target specific tools instead of auto-detection.
     #[clap(visible_alias = "update", visible_alias = "add")]
     Install,
     /// Remove Railway skills from all tools
@@ -101,6 +101,12 @@ pub(super) fn coding_tools(home: &Path) -> Vec<CodingTool> {
             global_parent: home.join(".cursor"),
             skills_dir_name: "skills",
         },
+        CodingTool {
+            slug: "pi",
+            name: "Pi",
+            global_parent: home.join(".pi").join("agent"),
+            skills_dir_name: "skills",
+        },
     ]
 }
 
@@ -433,4 +439,19 @@ mod tests {
         assert!(skills_configured_for_slug(home.path(), "copilot"));
         assert!(skills_configured_for_slug(home.path(), "factory-droid"));
     }
+
+    #[test]
+    fn detects_pi_skills() {
+        let home = tempfile::tempdir().unwrap();
+        std::fs::create_dir_all(
+            home.path()
+                .join(".pi")
+                .join("agent")
+                .join("skills")
+                .join("use-railway"),
+        )
+        .unwrap();
+
+        assert!(skills_configured_for_slug(home.path(), "pi"));
+    }
 }

src/main.rs

@@ -663,6 +663,8 @@ mod cli_tests {
             assert_parses(&["mcp", "install", "--remote"]);
             assert_parses(&["mcp", "install", "--remote", "--agent", "cursor"]);
             assert_parses(&["mcp", "install", "--remote", "--agent", "codex"]);
+            assert_parses(&["mcp", "install", "--agent", "pi"]);
+            assert_parses(&["mcp", "install", "--remote", "--agent", "pi"]);
         }
     }
 }