Rename .dot files to .fabro and update all references

Rename 79 workflow files from .dot to .fabro extension across
fabro/workflows/, test/, test/docs/, and files-internal/demo/.
Update TOML configs, Rust production code, test code, and shell
scripts. Backward compat tests in test/attractor/ are unchanged.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

fabro/workflows/daytona-check/run.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Run cargo check in a Daytona cloud sandbox"
-graph = "check.dot"
+graph = "check.fabro"
 
 [llm]
 model = "claude-sonnet"

fabro/workflows/golden-gate/workflow.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Create a hyperrealistic interactive 3D Golden Gate Bridge flight experience"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [llm]
 model = "gpt-5.4"

fabro/workflows/hello/workflow.toml

@@ -1,5 +1,5 @@
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "local"

fabro/workflows/imagegen-openai/workflow.toml

@@ -1,5 +1,5 @@
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"

fabro/workflows/imagegen/workflow.toml

@@ -1,5 +1,5 @@
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"

fabro/workflows/implement/workflow.toml

@@ -1,5 +1,5 @@
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "local"

fabro/workflows/playwright-demo/workflow.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Browse Hacker News with Playwright MCP and capture screenshots"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [llm]
 model = "claude-sonnet-4-6"

fabro/workflows/repl/workflow.toml

@@ -1,5 +1,5 @@
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "local"

fabro/workflows/solitaire/workflow.toml

@@ -1,2 +1,2 @@
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"

fabro/workflows/vnc-demo/workflow.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Browse the web with Playwright while user watches via VNC"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [llm]
 model = "claude-sonnet-4-6"

fabro/workflows/web-game-demo/workflow.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Verify the develop-web-game skill is properly set up with its asset files"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [llm]
 model = "claude-sonnet-4-6"

files-internal/demo/14-search-imagegen.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Search the web for a famous landmark, then generate an image of it"
-graph = "14-search-imagegen.dot"
+graph = "14-search-imagegen.fabro"
 
 [sandbox]
 provider = "daytona"

lib/crates/fabro-api/src/demo/mod.rs

@@ -1303,7 +1303,7 @@ mod runs {
         serde_json::to_value(fabro_workflows::cli::run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("Add rate limiting to auth endpoints".into()),
-            graph: "implement.dot".into(),
+            graph: "implement.fabro".into(),
             directory: Some("/workspace/api-server".into()),
             llm: Some(fabro_workflows::cli::run_config::LlmConfig {
                 model: Some("claude-opus-4-6".into()),
@@ -1415,7 +1415,7 @@ mod workflows {
             WorkflowListItem {
                 name: "Fix Build".into(),
                 slug: "fix_build".into(),
-                filename: "fix_build.dot".into(),
+                filename: "fix_build.fabro".into(),
                 last_run: Some(WorkflowLastRun {
                     ran_at: ts("2025-09-15T12:00:00Z"),
                 }),
@@ -1424,7 +1424,7 @@ mod workflows {
             WorkflowListItem {
                 name: "Implement Feature".into(),
                 slug: "implement".into(),
-                filename: "implement.dot".into(),
+                filename: "implement.fabro".into(),
                 last_run: Some(WorkflowLastRun {
                     ran_at: ts("2025-09-11T10:00:00Z"),
                 }),
@@ -1433,7 +1433,7 @@ mod workflows {
             WorkflowListItem {
                 name: "Sync Drift".into(),
                 slug: "sync_drift".into(),
-                filename: "sync_drift.dot".into(),
+                filename: "sync_drift.fabro".into(),
                 last_run: Some(WorkflowLastRun {
                     ran_at: ts("2025-09-14T14:00:00Z"),
                 }),
@@ -1442,7 +1442,7 @@ mod workflows {
             WorkflowListItem {
                 name: "Expand Product".into(),
                 slug: "expand".into(),
-                filename: "expand.dot".into(),
+                filename: "expand.fabro".into(),
                 last_run: Some(WorkflowLastRun {
                     ran_at: ts("2025-09-01T08:00:00Z"),
                 }),
@@ -1475,12 +1475,12 @@ mod workflows {
     pub fn detail(name: &str) -> Option<WorkflowDetail> {
         let items = [
             WorkflowDetail {
-                name: "Fix Build".into(), slug: "fix_build".into(), filename: "fix_build.dot".into(),
+                name: "Fix Build".into(), slug: "fix_build".into(), filename: "fix_build.fabro".into(),
                 description: "Automatically diagnoses and fixes CI build failures by analyzing error logs, identifying root causes, and applying targeted code changes.".into(),
                 config: run_config_to_api(fabro_workflows::cli::run_config::WorkflowRunConfig {
                     version: 1,
                     goal: Some("Diagnose and fix CI build failures".into()),
-                    graph: "fix_build.dot".into(),
+                    graph: "fix_build.fabro".into(),
                     directory: None,
                     llm: Some(fabro_workflows::cli::run_config::LlmConfig {
                         model: Some("claude-sonnet".into()),
@@ -1543,12 +1543,12 @@ mod workflows {
 "#.into(),
             },
             WorkflowDetail {
-                name: "Implement Feature".into(), slug: "implement".into(), filename: "implement.dot".into(),
+                name: "Implement Feature".into(), slug: "implement".into(), filename: "implement.fabro".into(),
                 description: "Generates production-ready code from a technical blueprint, including tests, documentation, and a pull request ready for review.".into(),
                 config: run_config_to_api(fabro_workflows::cli::run_config::WorkflowRunConfig {
                     version: 1,
                     goal: Some("Implement feature from technical blueprint".into()),
-                    graph: "implement.dot".into(),
+                    graph: "implement.fabro".into(),
                     directory: None,
                     llm: Some(fabro_workflows::cli::run_config::LlmConfig {
                         model: Some("claude-sonnet".into()),
@@ -1629,12 +1629,12 @@ mod workflows {
 "#.into(),
             },
             WorkflowDetail {
-                name: "Sync Drift".into(), slug: "sync_drift".into(), filename: "sync_drift.dot".into(),
+                name: "Sync Drift".into(), slug: "sync_drift".into(), filename: "sync_drift.fabro".into(),
                 description: "Detects configuration and code drift between environments, then generates reconciliation patches to bring everything back in sync.".into(),
                 config: run_config_to_api(fabro_workflows::cli::run_config::WorkflowRunConfig {
                     version: 1,
                     goal: Some("Detect and reconcile configuration drift across environments".into()),
-                    graph: "sync_drift.dot".into(),
+                    graph: "sync_drift.fabro".into(),
                     directory: None,
                     llm: Some(fabro_workflows::cli::run_config::LlmConfig {
                         model: Some("claude-sonnet".into()),
@@ -1703,12 +1703,12 @@ mod workflows {
 "#.into(),
             },
             WorkflowDetail {
-                name: "Expand Product".into(), slug: "expand".into(), filename: "expand.dot".into(),
+                name: "Expand Product".into(), slug: "expand".into(), filename: "expand.fabro".into(),
                 description: "Evolves the product by analyzing usage patterns and specifications to propose and implement incremental improvements.".into(),
                 config: run_config_to_api(fabro_workflows::cli::run_config::WorkflowRunConfig {
                     version: 1,
                     goal: Some("Propose and implement incremental product improvements".into()),
-                    graph: "expand.dot".into(),
+                    graph: "expand.fabro".into(),
                     directory: None,
                     llm: Some(fabro_workflows::cli::run_config::LlmConfig {
                         model: Some("claude-sonnet".into()),

lib/crates/fabro-cli/src/init.rs

@@ -58,8 +58,8 @@ root = \"fabro/\"
     std::fs::create_dir_all(&workflow_dir)
         .with_context(|| format!("failed to create {}", workflow_dir.display()))?;
 
-    // Create workflow.dot
-    let dot_path = workflow_dir.join("workflow.dot");
+    // Create workflow.fabro
+    let dot_path = workflow_dir.join("workflow.fabro");
     std::fs::write(
         &dot_path,
         r#"digraph Hello {
@@ -79,14 +79,14 @@ root = \"fabro/\"
     eprintln!(
         "  {} {}",
         green.apply_to("✔"),
-        dim.apply_to("arc/workflows/hello/workflow.dot")
+        dim.apply_to("arc/workflows/hello/workflow.fabro")
     );
 
     // Create workflow.toml
     let toml_path = workflow_dir.join("workflow.toml");
     std::fs::write(
         &toml_path,
-        "version = 1\ngraph = \"workflow.dot\"\n\n[sandbox]\nprovider = \"local\"\n",
+        "version = 1\ngraph = \"workflow.fabro\"\n\n[sandbox]\nprovider = \"local\"\n",
     )
     .with_context(|| format!("failed to write {}", toml_path.display()))?;
     eprintln!(

lib/crates/fabro-cli/tests/cli.rs

@@ -373,7 +373,7 @@ fn dry_run_writes_jsonl_and_live_json() {
             "--auto-approve",
             "--run-dir",
             run_dir.to_str().unwrap(),
-            "../../../test/simple.dot",
+            "../../../test/simple.fabro",
         ])
         .assert()
         .success();

lib/crates/fabro-cli/tests/cmd/run/dry-run-branching.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["run", "--dry-run", "--auto-approve", "../../../test/branching.dot"]
+args = ["run", "--dry-run", "--auto-approve", "../../../test/branching.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/run/dry-run-conditions.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["run", "--dry-run", "--auto-approve", "../../../test/conditions.dot"]
+args = ["run", "--dry-run", "--auto-approve", "../../../test/conditions.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/run/dry-run-legacy-tool.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["run", "--dry-run", "--auto-approve", "../../../test/legacy_tool.dot"]
+args = ["run", "--dry-run", "--auto-approve", "../../../test/legacy_tool.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/run/dry-run-parallel.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["run", "--dry-run", "--auto-approve", "../../../test/parallel.dot"]
+args = ["run", "--dry-run", "--auto-approve", "../../../test/parallel.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/run/dry-run-simple.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["run", "--dry-run", "--auto-approve", "../../../test/simple.dot"]
+args = ["run", "--dry-run", "--auto-approve", "../../../test/simple.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/run/dry-run-styled.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["run", "--dry-run", "--auto-approve", "../../../test/styled.dot"]
+args = ["run", "--dry-run", "--auto-approve", "../../../test/styled.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/validate/branching.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/branching.dot"]
+args = ["validate", "../../../test/branching.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/validate/conditions.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/conditions.dot"]
+args = ["validate", "../../../test/conditions.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/validate/invalid.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/invalid.dot"]
+args = ["validate", "../../../test/invalid.fabro"]
 status = "failed"
 
 [fs]

lib/crates/fabro-cli/tests/cmd/validate/legacy-tool.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/legacy_tool.dot"]
+args = ["validate", "../../../test/legacy_tool.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/validate/parallel.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/parallel.dot"]
+args = ["validate", "../../../test/parallel.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/validate/simple.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/simple.dot"]
+args = ["validate", "../../../test/simple.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-cli/tests/cmd/validate/styled.toml

@@ -1,5 +1,5 @@
 bin.name = "fabro"
-args = ["validate", "../../../test/styled.dot"]
+args = ["validate", "../../../test/styled.fabro"]
 
 [fs]
 sandbox = false

lib/crates/fabro-workflows/src/cli/graph.rs

@@ -11,7 +11,7 @@ use tracing::debug;
 use crate::validation::Severity;
 use crate::workflow::prepare_from_file;
 
-use super::{print_diagnostics, read_dot_file, relative_path};
+use super::{print_diagnostics, read_workflow_file, relative_path};
 
 /// Output format for graph rendering.
 #[derive(Debug, Clone, Copy, Default, ValueEnum)]
@@ -34,7 +34,7 @@ impl fmt::Display for GraphFormat {
 
 #[derive(Args)]
 pub struct GraphArgs {
-    /// Path to the .dot workflow file, .toml task config, or project workflow name
+    /// Path to the .fabro workflow file, .toml task config, or project workflow name
     pub workflow: PathBuf,
 
     /// Output format
@@ -58,7 +58,7 @@ pub fn graph_command(args: &GraphArgs, styles: &Styles) -> anyhow::Result<()> {
         bail!("Validation failed");
     }
 
-    let source = read_dot_file(&dot_path)?;
+    let source = read_workflow_file(&dot_path)?;
     let rendered = render_dot(&source, args.format)?;
 
     if let Some(ref output_path) = args.output {
@@ -140,7 +140,7 @@ mod tests {
     #[test]
     fn graph_missing_file() {
         let args = GraphArgs {
-            workflow: PathBuf::from("/tmp/nonexistent_workflow_99999.dot"),
+            workflow: PathBuf::from("/tmp/nonexistent_workflow_99999.fabro"),
             format: GraphFormat::Svg,
             output: None,
         };
@@ -151,7 +151,10 @@ mod tests {
 
     #[test]
     fn graph_invalid_syntax() {
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(tmp, "not a valid dot file").unwrap();
 
         let args = GraphArgs {
@@ -171,7 +174,10 @@ mod tests {
             return;
         }
 
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(tmp, "{VALID_DOT}").unwrap();
 
         let output_dir = tempfile::tempdir().unwrap();
@@ -197,7 +203,10 @@ mod tests {
             return;
         }
 
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(tmp, "{VALID_DOT}").unwrap();
 
         let output_dir = tempfile::tempdir().unwrap();
@@ -227,7 +236,10 @@ mod tests {
             return;
         }
 
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(tmp, "{VALID_DOT}").unwrap();
 
         let output_dir = tempfile::tempdir().unwrap();
@@ -258,10 +270,10 @@ mod tests {
         std::fs::create_dir_all(&wf_dir).unwrap();
         std::fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"workflow.dot\"\n",
+            "version = 1\ngraph = \"workflow.fabro\"\n",
         )
         .unwrap();
-        std::fs::write(wf_dir.join("workflow.dot"), VALID_DOT).unwrap();
+        std::fs::write(wf_dir.join("workflow.fabro"), VALID_DOT).unwrap();
 
         let output_dir = tempfile::tempdir().unwrap();
         let output_path = output_dir.path().join("out.svg");

lib/crates/fabro-workflows/src/cli/mod.rs

@@ -87,7 +87,7 @@ impl FromStr for SandboxProvider {
 #[command(
     name = "fabro-workflows",
     version,
-    about = "DOT-based workflow runner for AI workflows"
+    about = "Workflow runner for AI workflows"
 )]
 pub struct Cli {
     #[command(subcommand)]
@@ -96,7 +96,7 @@ pub struct Cli {
 
 #[derive(Subcommand)]
 pub enum Command {
-    /// Launch a workflow from a .dot or .toml task file
+    /// Launch a workflow from a .fabro or .toml task file
     Run(RunArgs),
     /// Parse and validate a workflow without executing
     Validate(ValidateArgs),
@@ -104,7 +104,7 @@ pub enum Command {
 
 #[derive(Args)]
 pub struct RunArgs {
-    /// Path to a .dot workflow file or .toml task config (not required with --run-branch)
+    /// Path to a .fabro workflow file or .toml task config (not required with --run-branch)
     #[arg(required_unless_present = "run_branch")]
     pub workflow: Option<PathBuf>,
 
@@ -175,22 +175,22 @@ pub struct RunArgs {
 
 #[derive(Args)]
 pub struct ValidateArgs {
-    /// Path to the .dot workflow file
+    /// Path to the .fabro workflow file
     pub workflow: PathBuf,
 }
 
 #[derive(Args)]
 pub struct ParseArgs {
-    /// Path to the .dot workflow file
+    /// Path to the .fabro workflow file
     pub workflow: PathBuf,
 }
 
-/// Read a .dot file from disk.
+/// Read a workflow file from disk.
 ///
 /// # Errors
 ///
 /// Returns an error if the file cannot be read.
-pub fn read_dot_file(path: &Path) -> anyhow::Result<String> {
+pub fn read_workflow_file(path: &Path) -> anyhow::Result<String> {
     std::fs::read_to_string(path)
         .map_err(|e| anyhow::anyhow!("Failed to read {}: {e}", path.display()))
 }

lib/crates/fabro-workflows/src/cli/parse.rs

@@ -1,6 +1,6 @@
 use std::io::Write;
 
-use super::{read_dot_file, ParseArgs};
+use super::{read_workflow_file, ParseArgs};
 
 /// Parse a DOT file and print its raw AST as JSON.
 ///
@@ -14,7 +14,7 @@ pub fn parse_command(args: &ParseArgs) -> anyhow::Result<()> {
 
 fn parse_command_to(args: &ParseArgs, mut out: impl Write) -> anyhow::Result<()> {
     let (dot_path, _cfg) = super::project_config::resolve_workflow(&args.workflow)?;
-    let source = read_dot_file(&dot_path)?;
+    let source = read_workflow_file(&dot_path)?;
     let ast = crate::parser::parse_ast(&source)?;
     serde_json::to_writer_pretty(&mut out, &ast)?;
     writeln!(out)?;
@@ -30,7 +30,10 @@ mod tests {
 
     #[test]
     fn parse_command_outputs_json_ast() {
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(
             tmp,
             r#"digraph Hello {{
@@ -54,7 +57,10 @@ mod tests {
 
     #[test]
     fn parse_command_rejects_invalid_dot() {
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(tmp, "not a valid dot file").unwrap();
 
         let args = ParseArgs {
@@ -71,11 +77,11 @@ mod tests {
         std::fs::create_dir_all(&wf_dir).unwrap();
         std::fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"workflow.dot\"\n",
+            "version = 1\ngraph = \"workflow.fabro\"\n",
         )
         .unwrap();
         std::fs::write(
-            wf_dir.join("workflow.dot"),
+            wf_dir.join("workflow.fabro"),
             r#"digraph Hello {
     start [shape=Mdiamond]
     exit [shape=Msquare]
@@ -97,7 +103,7 @@ mod tests {
     #[test]
     fn parse_command_rejects_missing_file() {
         let args = ParseArgs {
-            workflow: PathBuf::from("/tmp/nonexistent_parse_test_12345.dot"),
+            workflow: PathBuf::from("/tmp/nonexistent_parse_test_12345.fabro"),
         };
         let result = parse_command_to(&args, Vec::new());
         assert!(result.is_err(), "expected Err for missing file");

lib/crates/fabro-workflows/src/cli/project_config.rs

@@ -80,7 +80,7 @@ pub fn discover_project_config(start: &Path) -> anyhow::Result<Option<(PathBuf,
 
 /// Resolve a workflow argument to a path.
 ///
-/// - If the arg has a file extension (`.toml`, `.dot`, etc.), return it as-is.
+/// - If the arg has a file extension (`.toml`, `.fabro`, etc.), return it as-is.
 /// - If no extension, attempt project-based resolution: find `fabro.toml`, resolve
 ///   `{fabro_root}/workflows/{name}/workflow.toml`. Returns an error with suggestions
 ///   if an `fabro.toml` exists but the workflow wasn't found.
@@ -345,10 +345,10 @@ mod tests {
     }
 
     #[test]
-    fn resolve_workflow_arg_dot_extension_returned_as_is() {
+    fn resolve_workflow_arg_fabro_extension_returned_as_is() {
         let tmp = TempDir::new().unwrap();
-        let result = resolve_workflow_arg_from(Path::new("my-workflow.dot"), tmp.path()).unwrap();
-        assert_eq!(result, Path::new("my-workflow.dot"));
+        let result = resolve_workflow_arg_from(Path::new("my-workflow.fabro"), tmp.path()).unwrap();
+        assert_eq!(result, Path::new("my-workflow.fabro"));
     }
 
     #[test]
@@ -366,7 +366,7 @@ mod tests {
         fs::create_dir_all(&wf_dir).unwrap();
         fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"workflow.dot\"\n",
+            "version = 1\ngraph = \"workflow.fabro\"\n",
         )
         .unwrap();
 
@@ -382,7 +382,7 @@ mod tests {
         fs::create_dir_all(&wf_dir).unwrap();
         fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"w.dot\"\n",
+            "version = 1\ngraph = \"w.fabro\"\n",
         )
         .unwrap();
 
@@ -400,7 +400,7 @@ mod tests {
         fs::create_dir_all(&wf_dir).unwrap();
         fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"w.dot\"\n",
+            "version = 1\ngraph = \"w.fabro\"\n",
         )
         .unwrap();
 
@@ -433,7 +433,7 @@ mod tests {
         fs::create_dir_all(&wf_dir).unwrap();
         fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"workflow.dot\"\n",
+            "version = 1\ngraph = \"workflow.fabro\"\n",
         )
         .unwrap();
 
@@ -441,7 +441,7 @@ mod tests {
         assert_eq!(result, wf_dir.join("workflow.toml"));
     }
 
-    /// Helper: create a temp dir with fabro.toml + workflows/{name}/{workflow.toml, workflow.dot}
+    /// Helper: create a temp dir with fabro.toml + workflows/{name}/{workflow.toml, workflow.fabro}
     /// and chdir into it so `resolve_workflow` (which uses cwd) can find the config.
     fn setup_workflow_project(name: &str) -> (TempDir, PathBuf) {
         let tmp = TempDir::new().unwrap();
@@ -450,15 +450,15 @@ mod tests {
         fs::create_dir_all(&wf_dir).unwrap();
         fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"workflow.dot\"\n",
+            "version = 1\ngraph = \"workflow.fabro\"\n",
         )
         .unwrap();
         fs::write(
-            wf_dir.join("workflow.dot"),
+            wf_dir.join("workflow.fabro"),
             "digraph G { start [shape=Mdiamond]; exit [shape=Msquare]; start -> exit }",
         )
         .unwrap();
-        let dot_path = wf_dir.join("workflow.dot");
+        let dot_path = wf_dir.join("workflow.fabro");
         (tmp, dot_path)
     }
 
@@ -483,10 +483,10 @@ mod tests {
     }
 
     #[test]
-    fn resolve_workflow_dot_path() {
+    fn resolve_workflow_fabro_path() {
         let (tmp, expected_dot) = setup_workflow_project("hello");
         let (dot_path, cfg) = resolve_workflow_from(&expected_dot, tmp.path()).unwrap();
         assert_eq!(dot_path, expected_dot);
-        assert!(cfg.is_none(), "expected None for .dot path");
+        assert!(cfg.is_none(), "expected None for .fabro path");
     }
 }

lib/crates/fabro-workflows/src/cli/run.rs

@@ -34,7 +34,7 @@ use indicatif::HumanDuration;
 use std::time::Duration;
 
 use super::{
-    compute_stage_cost, format_cost, format_tokens_human, print_diagnostics, read_dot_file,
+    compute_stage_cost, format_cost, format_tokens_human, print_diagnostics, read_workflow_file,
     RunArgs, SandboxProvider,
 };
 
@@ -349,7 +349,7 @@ pub async fn run_command(
         .unwrap_or_default();
 
     // 1. Parse and validate workflow
-    let source = read_dot_file(&dot_path)?;
+    let source = read_workflow_file(&dot_path)?;
     let vars = run_cfg
         .as_ref()
         .and_then(|c| c.vars.as_ref())
@@ -2524,7 +2524,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".to_string()),
-            graph: "test.dot".to_string(),
+            graph: "test.fabro".to_string(),
             directory: None,
             llm: Some(run_config::LlmConfig {
                 model: Some("toml-model".to_string()),
@@ -2568,7 +2568,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".to_string()),
-            graph: "test.dot".to_string(),
+            graph: "test.fabro".to_string(),
             directory: None,
             llm: Some(run_config::LlmConfig {
                 model: Some("toml-model".to_string()),
@@ -2647,7 +2647,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".to_string()),
-            graph: "test.dot".to_string(),
+            graph: "test.fabro".to_string(),
             directory: None,
             llm: Some(run_config::LlmConfig {
                 model: Some("toml-model".to_string()),
@@ -2673,7 +2673,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".to_string()),
-            graph: "w.dot".into(),
+            graph: "w.fabro".into(),
             directory: None,
             llm: None,
             setup: None,
@@ -2704,7 +2704,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".to_string()),
-            graph: "w.dot".into(),
+            graph: "w.fabro".into(),
             directory: None,
             llm: None,
             setup: None,
@@ -2782,7 +2782,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".into()),
-            graph: "w.dot".into(),
+            graph: "w.fabro".into(),
             directory: None,
             llm: None,
             setup: None,
@@ -2842,7 +2842,7 @@ mod tests {
         let cfg = run_config::WorkflowRunConfig {
             version: 1,
             goal: Some("test".into()),
-            graph: "w.dot".into(),
+            graph: "w.fabro".into(),
             directory: None,
             llm: None,
             setup: None,

lib/crates/fabro-workflows/src/cli/run_config.rs

@@ -441,7 +441,7 @@ mod tests {
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [vars]
 repo_url = "https://github.com/org/repo"
@@ -522,7 +522,7 @@ language = "python"
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -538,7 +538,7 @@ devcontainer = true
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -553,7 +553,7 @@ provider = "daytona"
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -569,7 +569,7 @@ provider = "daytona"
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -614,7 +614,7 @@ dockerfile = "FROM rust:1.85-slim-bookworm\nRUN apt-get update"
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -633,12 +633,12 @@ auto_stop_interval = 30
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 "#;
         let config = parse_run_config(toml).unwrap();
         assert_eq!(config.version, 1);
         assert_eq!(config.goal.as_deref(), Some("Run tests"));
-        assert_eq!(config.graph, "workflow.dot");
+        assert_eq!(config.graph, "workflow.fabro");
         assert!(config.directory.is_none());
         assert!(config.llm.is_none());
         assert!(config.setup.is_none());
@@ -648,7 +648,7 @@ graph = "workflow.dot"
     fn parse_toml_without_goal() {
         let toml = r#"
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 "#;
         let config = parse_run_config(toml).unwrap();
         assert!(config.goal.is_none());
@@ -659,7 +659,7 @@ graph = "workflow.dot"
         let toml = r#"
 version = 1
 goal = "Full workflow"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 directory = "/tmp/repo"
 
 [llm]
@@ -688,7 +688,7 @@ timeout_ms = 60000
         let toml = r#"
 version = 2
 goal = "x"
-graph = "p.dot"
+graph = "p.fabro"
 "#;
         let err = parse_run_config(toml).unwrap_err();
         assert!(
@@ -700,22 +700,22 @@ graph = "p.dot"
     #[test]
     fn graph_path_resolved_relative_to_toml() {
         let toml_path = Path::new("/tmp/sub/task.toml");
-        let resolved = resolve_graph_path(toml_path, "p.dot");
-        assert_eq!(resolved, PathBuf::from("/tmp/sub/p.dot"));
+        let resolved = resolve_graph_path(toml_path, "p.fabro");
+        assert_eq!(resolved, PathBuf::from("/tmp/sub/p.fabro"));
     }
 
     #[test]
     fn graph_path_absolute_unchanged() {
         let toml_path = Path::new("/tmp/sub/task.toml");
-        let resolved = resolve_graph_path(toml_path, "/other/workflow.dot");
-        assert_eq!(resolved, PathBuf::from("/other/workflow.dot"));
+        let resolved = resolve_graph_path(toml_path, "/other/workflow.fabro");
+        assert_eq!(resolved, PathBuf::from("/other/workflow.fabro"));
     }
 
     #[test]
     fn goal_is_optional() {
         let no_goal = r#"
 version = 1
-graph = "p.dot"
+graph = "p.fabro"
 "#;
         let config = parse_run_config(no_goal).unwrap();
         assert!(config.goal.is_none());
@@ -735,7 +735,7 @@ goal = "x"
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox.daytona.snapshot]
 name = "my-snapshot"
@@ -767,7 +767,7 @@ dockerfile = { path = "./Dockerfile" }
             r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox.daytona.snapshot]
 name = "my-snapshot"
@@ -795,7 +795,7 @@ dockerfile = { path = "Dockerfile" }
             r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox.daytona.snapshot]
 name = "my-snapshot"
@@ -867,7 +867,7 @@ key = "value"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#,
         )
         .unwrap();
@@ -890,7 +890,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [llm]
 model = "task-model"
@@ -916,7 +916,7 @@ model = "task-model"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [vars]
 task_key = "task_val"
@@ -945,7 +945,7 @@ shared = "from_task"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#,
         )
         .unwrap();
@@ -964,7 +964,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [llm]
 model = "haiku"
@@ -991,7 +991,7 @@ model = "haiku"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [setup]
 commands = ["make test"]
@@ -1016,7 +1016,7 @@ commands = ["make test"]
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "docker"
@@ -1032,7 +1032,7 @@ preserve = true
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [sandbox]
 provider = "docker"
@@ -1047,7 +1047,7 @@ provider = "docker"
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.local]
 worktree_mode = "always"
@@ -1062,7 +1062,7 @@ worktree_mode = "always"
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 provider = "local"
@@ -1077,7 +1077,7 @@ provider = "local"
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.local]
 "#;
@@ -1092,7 +1092,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 preserve = true
@@ -1123,7 +1123,7 @@ preserve = true
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 provider = "docker"
@@ -1154,7 +1154,7 @@ provider = "docker"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -1191,7 +1191,7 @@ provider = "daytona"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -1231,7 +1231,7 @@ auto_stop_interval = 60
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.daytona.labels]
 project = "fabro"
@@ -1272,7 +1272,7 @@ env = "from_task"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.daytona.snapshot]
 name = "task-snap"
@@ -1316,7 +1316,7 @@ cpu = 2
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.daytona]
 auto_stop_interval = 60
@@ -1358,7 +1358,7 @@ auto_stop_interval = 60
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [llm]
 model = "claude-opus-4-6"
@@ -1380,7 +1380,7 @@ gemini = ["anthropic", "openai"]
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [llm]
 model = "claude-opus-4-6"
@@ -1397,7 +1397,7 @@ provider = "anthropic"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [llm]
 model = "opus"
@@ -1426,7 +1426,7 @@ anthropic = ["gemini"]
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [llm]
 model = "opus"
@@ -1489,7 +1489,7 @@ model = "opus"
         let toml = r#"
 version = 1
 goal = "Test hooks"
-graph = "test.dot"
+graph = "test.fabro"
 
 [[hooks]]
 event = "stage_start"
@@ -1518,7 +1518,7 @@ command = "echo done"
         let toml = r#"
 version = 1
 goal = "No hooks"
-graph = "test.dot"
+graph = "test.fabro"
 "#;
         let cfg: WorkflowRunConfig = toml::from_str(toml).unwrap();
         assert!(cfg.hooks.is_empty());
@@ -1529,7 +1529,7 @@ graph = "test.dot"
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.daytona]
 network = "block"
@@ -1548,7 +1548,7 @@ network = "block"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.daytona]
 network = "block"
@@ -1585,7 +1585,7 @@ network = "block"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.daytona]
 auto_stop_interval = 60
@@ -1625,7 +1625,7 @@ auto_stop_interval = 60
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [checkpoint]
 exclude_globs = ["**/node_modules/**", "**/.cache/**"]
@@ -1642,7 +1642,7 @@ exclude_globs = ["**/node_modules/**", "**/.cache/**"]
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#;
         let config = parse_run_config(toml).unwrap();
         assert!(config.checkpoint.exclude_globs.is_empty());
@@ -1654,7 +1654,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [checkpoint]
 exclude_globs = ["**/dist/**", "**/.cache/**"]
@@ -1680,7 +1680,7 @@ exclude_globs = ["**/dist/**", "**/.cache/**"]
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#,
         )
         .unwrap();
@@ -1700,7 +1700,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [checkpoint]
 exclude_globs = ["**/dist/**"]
@@ -1730,7 +1730,7 @@ exclude_globs = ["**/node_modules/**"]
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.env]
 FOO = "bar"
@@ -1748,7 +1748,7 @@ BAZ = "${env.HOME}"
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -1800,7 +1800,7 @@ provider = "daytona"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.env]
 TASK_KEY = "task_val"
@@ -1838,7 +1838,7 @@ SHARED = "from_task"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox]
 provider = "daytona"
@@ -1874,7 +1874,7 @@ provider = "daytona"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.env]
 LITERAL = "hello"
@@ -1899,7 +1899,7 @@ FROM_HOST = "${env.FABRO_TEST_LOAD_ENV}"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [sandbox.env]
 MISSING = "${env.FABRO_TEST_DEFINITELY_NOT_SET_67890}"
@@ -1920,7 +1920,7 @@ MISSING = "${env.FABRO_TEST_DEFINITELY_NOT_SET_67890}"
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [pull_request]
 enabled = true
@@ -1935,7 +1935,7 @@ enabled = true
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#;
         let config = parse_run_config(toml).unwrap();
         assert!(config.pull_request.is_none());
@@ -1947,7 +1947,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [pull_request]
 enabled = true
@@ -1971,7 +1971,7 @@ enabled = true
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#,
         )
         .unwrap();
@@ -2001,7 +2001,7 @@ enabled = true
         let toml = r#"
 version = 1
 goal = "Run tests"
-graph = "workflow.dot"
+graph = "workflow.fabro"
 
 [assets]
 include = ["test-results/**", "playwright-report/**", "*.trace.zip"]
@@ -2018,7 +2018,7 @@ include = ["test-results/**", "playwright-report/**", "*.trace.zip"]
     fn parse_toml_without_assets() {
         let toml = r#"
 version = 1
-graph = "workflow.dot"
+graph = "workflow.fabro"
 "#;
         let config = parse_run_config(toml).unwrap();
         assert!(config.assets.is_none());
@@ -2030,7 +2030,7 @@ graph = "workflow.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 "#,
         )
         .unwrap();
@@ -2051,7 +2051,7 @@ graph = "w.dot"
             r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [assets]
 include = ["playwright-report/**"]
@@ -2074,7 +2074,7 @@ include = ["playwright-report/**"]
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [pull_request]
 enabled = true
@@ -2091,7 +2091,7 @@ draft = true
         let toml = r#"
 version = 1
 goal = "test"
-graph = "w.dot"
+graph = "w.fabro"
 
 [pull_request]
 enabled = true

lib/crates/fabro-workflows/src/cli/validate.rs

@@ -46,7 +46,10 @@ mod tests {
 
     #[test]
     fn validate_valid_workflow() {
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(
             tmp,
             r#"digraph Simple {{
@@ -74,7 +77,10 @@ mod tests {
 
     #[test]
     fn validate_invalid_syntax() {
-        let mut tmp = tempfile::Builder::new().suffix(".dot").tempfile().unwrap();
+        let mut tmp = tempfile::Builder::new()
+            .suffix(".fabro")
+            .tempfile()
+            .unwrap();
         write!(tmp, "not a valid dot file").unwrap();
 
         let args = ValidateArgs {
@@ -101,8 +107,8 @@ mod tests {
         std::fs::create_dir_all(&prompts_dir).unwrap();
         std::fs::write(prompts_dir.join("plan.md"), "Plan the work carefully.").unwrap();
 
-        // Write a .dot file that uses @prompts/plan.md
-        let dot_path = dir.path().join("workflow.dot");
+        // Write a .fabro file that uses @prompts/plan.md
+        let dot_path = dir.path().join("workflow.fabro");
         std::fs::write(
             &dot_path,
             r#"digraph FileRef {
@@ -128,11 +134,11 @@ mod tests {
         std::fs::create_dir_all(&wf_dir).unwrap();
         std::fs::write(
             wf_dir.join("workflow.toml"),
-            "version = 1\ngraph = \"workflow.dot\"\n",
+            "version = 1\ngraph = \"workflow.fabro\"\n",
         )
         .unwrap();
         std::fs::write(
-            wf_dir.join("workflow.dot"),
+            wf_dir.join("workflow.fabro"),
             r#"digraph Hello {
     graph [goal="Test"]
     start [shape=Mdiamond]
@@ -154,7 +160,7 @@ mod tests {
     #[test]
     fn validate_missing_file() {
         let args = ValidateArgs {
-            workflow: PathBuf::from("/tmp/nonexistent_workflow_12345.dot"),
+            workflow: PathBuf::from("/tmp/nonexistent_workflow_12345.fabro"),
         };
         let styles = Styles::new(false);
         let result = validate_command(&args, &styles);

lib/crates/fabro-workflows/src/handler/manager_loop.rs

@@ -334,7 +334,7 @@ mod tests {
         assert!(outcome
             .failure_reason()
             .unwrap()
-            .contains("No child DOT source"));
+            .contains("No child workflow source"));
     }
 
     #[tokio::test]

lib/crates/fabro-workflows/src/pull_request.rs

@@ -602,7 +602,7 @@ mod tests {
         let dot = "digraph implement {\n  plan [type=\"agent\"]\n  code [type=\"agent\"]\n  plan -> code\n}\n";
         let section = format_arc_details_section(&conclusion, Some(dot));
 
-        assert!(section.contains("<code>implement.dot</code>"));
+        assert!(section.contains("<code>implement.fabro</code>"));
         assert!(section.contains("2 nodes and 1 edge"));
         assert!(section.contains("```dot"));
         assert!(section.contains("digraph implement"));
@@ -737,7 +737,7 @@ mod tests {
   plan -> code
 }"#;
         let (name, nodes, edges) = parse_dot_summary(dot);
-        assert_eq!(name, "my_workflow.dot");
+        assert_eq!(name, "my_workflow.fabro");
         assert_eq!(nodes, 2);
         assert_eq!(edges, 1);
     }
@@ -745,7 +745,7 @@ mod tests {
     #[test]
     fn parse_dot_summary_empty() {
         let (name, nodes, edges) = parse_dot_summary("");
-        assert_eq!(name, "workflow.dot");
+        assert_eq!(name, "workflow.fabro");
         assert_eq!(nodes, 0);
         assert_eq!(edges, 0);
     }

lib/crates/fabro-workflows/src/validation/rules.rs

@@ -997,7 +997,7 @@ impl LintRule for UnresolvedFileRefRule {
                         ),
                         node_id: Some(node.id.clone()),
                         edge: None,
-                        fix: Some("Check that the path is relative to the .dot file's directory and the file exists".to_string()),
+                        fix: Some("Check that the path is relative to the workflow file's directory and the file exists".to_string()),
                     });
                 }
             }
@@ -1011,7 +1011,7 @@ impl LintRule for UnresolvedFileRefRule {
                     message: format!("Graph goal has unresolved file reference: {goal}"),
                     node_id: None,
                     edge: None,
-                    fix: Some("Check that the path is relative to the .dot file's directory and the file exists".to_string()),
+                    fix: Some("Check that the path is relative to the workflow file's directory and the file exists".to_string()),
                 });
             }
         }

test/docs/execution/run-configuration/run-c-i.toml

@@ -1,6 +1,6 @@
 version = 1
 goal = "Run tests for $repo_name"
-graph = "c-i.dot"
+graph = "c-i.fabro"
 
 [vars]
 language = "test-language"

test/docs/run_tests.sh

@@ -35,7 +35,7 @@ run_one() {
 
     # Check for companion run.toml (run-<stem>.toml in same dir)
     local stem
-    stem="$(basename "${dot%.dot}")"
+    stem="$(basename "${dot%.fabro}")"
     local toml
     toml="${dot_dir}/run-${stem}.toml"
 
@@ -101,7 +101,7 @@ echo ""
 dots=()
 while IFS= read -r dot; do
     dots+=("$dot")
-done < <(find "$SCRIPT_DIR" -name '*.dot' | sort)
+done < <(find "$SCRIPT_DIR" -name '*.fabro' | sort)
 
 # Run with parallelism
 active=0