diff --git a/sdk/go/harness/coverage_branches_test.go b/sdk/go/harness/coverage_branches_test.go
index efc637b77..7770c1a5f 100644
--- a/sdk/go/harness/coverage_branches_test.go
+++ b/sdk/go/harness/coverage_branches_test.go
@@ -205,13 +205,15 @@ fi
 		assert.False(t, raw.IsError)
 		// $PWD reflects the subprocess working directory (Options.Cwd).
 		assert.Contains(t, raw.Result, dir)
-		// opencode 1.14+ surface: `run` subcommand, --dir for project, -m for
-		// model, --dangerously-skip-permissions for headless, prompt is
-		// positional. -c, -q, -p are deprecated/rebound (see issue #517).
+		// opencode 1.14+ surface: `run` subcommand, --dir for project, -m
+		// for model, prompt is positional. -c, -q, -p are
+		// deprecated/rebound (see issue #517). --dangerously-skip-permissions
+		// is rejected by `run` on v1.14 — opencode prints help and exits 0,
+		// see agentfield#582 — so it must NOT be on the command line.
 		assert.Contains(t, raw.Result, "run")
 		assert.Contains(t, raw.Result, "--dir /ignored/project")
 		assert.Contains(t, raw.Result, "-m stub-model")
-		assert.Contains(t, raw.Result, "--dangerously-skip-permissions")
+		assert.NotContains(t, raw.Result, "--dangerously-skip-permissions")
 		// Prompt is the last positional argument (no -p flag in front).
 		assert.Regexp(t, `\sprompt$`, strings.TrimSpace(raw.Result))
 		assert.NotContains(t, raw.Result, "-q ")
diff --git a/sdk/go/harness/opencode.go b/sdk/go/harness/opencode.go
index dab1b7076..378010900 100644
--- a/sdk/go/harness/opencode.go
+++ b/sdk/go/harness/opencode.go
@@ -75,8 +75,11 @@ func (p *OpenCodeProvider) Execute(ctx context.Context, prompt string, options O
 		cmd = append(cmd, "-m", options.Model)
 	}
 
-	// Skip the interactive permission prompt for headless execution.
-	cmd = append(cmd, "--dangerously-skip-permissions")
+	// opencode v1.14 does not accept --dangerously-skip-permissions on the
+	// `run` subcommand — passing it makes yargs print the run-help screen
+	// to stdout and exit 0, which the SDK then captures as the LLM
+	// response. opencode in non-TTY mode proceeds without permission
+	// prompting, so no flag is needed. See agentfield#582.
 
 	// Prepend system prompt if provided. OpenCode has no native
 	// --system-prompt flag, so inline it ahead of the user prompt.
diff --git a/sdk/python/agentfield/harness/providers/opencode.py b/sdk/python/agentfield/harness/providers/opencode.py
index 7bc161965..15968597b 100644
--- a/sdk/python/agentfield/harness/providers/opencode.py
+++ b/sdk/python/agentfield/harness/providers/opencode.py
@@ -163,8 +163,11 @@ async def _execute_impl(self, prompt: str, options: dict[str, object]) -> RawRes
         if options.get("model"):
             cmd.extend(["-m", str(options["model"])])
 
-        # Skip interactive permission prompts for headless execution
-        cmd.append("--dangerously-skip-permissions")
+        # opencode v1.14 does not accept --dangerously-skip-permissions on the
+        # `run` subcommand — passing it makes yargs print the run-help screen
+        # to stdout and exit 0, which the SDK then captures as the LLM
+        # response. opencode in non-TTY mode proceeds without permission
+        # prompting, so no flag is needed. See agentfield#582.
 
         # Handle system prompt - prepend to user prompt since OpenCode
         # has no native --system-prompt flag
diff --git a/sdk/python/tests/test_harness_provider_opencode.py b/sdk/python/tests/test_harness_provider_opencode.py
index cd793c73c..687177ca1 100644
--- a/sdk/python/tests/test_harness_provider_opencode.py
+++ b/sdk/python/tests/test_harness_provider_opencode.py
@@ -45,7 +45,6 @@ async def fake_run_cli(cmd, *, env=None, cwd=None, timeout=None):
         "json",
         "--dir",
         "/tmp/work",
-        "--dangerously-skip-permissions",
         "hello",
     ]
     assert captured["env"]["A"] == "1"
@@ -129,7 +128,6 @@ async def fake_run_cli(cmd, *, env=None, cwd=None, timeout=None):
         "json",
         "-m",
         "openai/gpt-5",
-        "--dangerously-skip-permissions",
         "hello",
     ]
     # Model is now passed via -m flag, not environment variable
@@ -400,8 +398,9 @@ async def capture_cmd(cmd, *, env=None, cwd=None, timeout=None):
     assert "--dir" in captured_cmd, "Must use --dir for project directory (v1.4+)"
     # Must use -m for model
     assert "-m" in captured_cmd, "Must use -m flag for model (v1.4+)"
-    # Must skip permissions for headless execution
-    assert "--dangerously-skip-permissions" in cmd_str
+    # Must NOT use --dangerously-skip-permissions: opencode v1.14 rejects it
+    # on `run` and prints help to stdout, see agentfield#582.
+    assert "--dangerously-skip-permissions" not in cmd_str
     # Prompt must be positional (last arg)
     assert captured_cmd[-1] == "build the feature"
 
diff --git a/sdk/typescript/src/harness/providers/opencode.ts b/sdk/typescript/src/harness/providers/opencode.ts
index 9f1d7cb31..f3262fce1 100644
--- a/sdk/typescript/src/harness/providers/opencode.ts
+++ b/sdk/typescript/src/harness/providers/opencode.ts
@@ -11,30 +11,36 @@ export class OpenCodeProvider implements HarnessProvider {
   }
 
   async execute(prompt: string, options: Record<string, unknown>): Promise<RawResult> {
-    const cmd = [this.bin];
+    // opencode v1.4+ uses the `run` subcommand. Prior `-c <dir> -p <prompt>`
+    // syntax is broken on v1.14: `-c` now means `--continue` (a boolean) and
+    // there is no top-level `-p` flag, so opencode prints help to stdout and
+    // exits 0 — the SDK then captures the help screen as the LLM response.
+    // See agentfield#582.
+    const cmd = [this.bin, 'run'];
 
-    // Use -c for cwd (project directory)
+    // Use --dir for project directory.
     if (options.cwd && typeof options.cwd === 'string') {
-      cmd.push('-c', options.cwd);
+      cmd.push('--dir', options.cwd);
     } else if (options.project_dir && typeof options.project_dir === 'string') {
-      cmd.push('-c', options.project_dir);
+      cmd.push('--dir', options.project_dir);
     }
 
-    // Model is set via environment variable, not CLI flag
     const env: Record<string, string> = { ...(options.env as Record<string, string>) };
+
+    // Pass model via -m flag on the run subcommand (not env var).
     if (options.model) {
-      env['MODEL'] = String(options.model);
+      cmd.push('-m', String(options.model));
     }
 
     // Handle system prompt - prepend to user prompt since OpenCode
-    // has no native --system-prompt flag
+    // has no native --system-prompt flag.
     let effectivePrompt = prompt;
     if (options.system_prompt && typeof options.system_prompt === 'string' && options.system_prompt.trim()) {
       effectivePrompt = `SYSTEM INSTRUCTIONS:\n${options.system_prompt.trim()}\n\n---\n\nUSER REQUEST:\n${prompt}`;
     }
 
-    // Use -p for single prompt mode (non-interactive)
-    cmd.push('-p', effectivePrompt);
+    // Prompt is the positional `message` arg to `opencode run`.
+    cmd.push(effectivePrompt);
 
     const startApi = Date.now();
     try {
diff --git a/sdk/typescript/tests/harness_provider_opencode.test.ts b/sdk/typescript/tests/harness_provider_opencode.test.ts
index df94ffa89..9ba0f6c59 100644
--- a/sdk/typescript/tests/harness_provider_opencode.test.ts
+++ b/sdk/typescript/tests/harness_provider_opencode.test.ts
@@ -22,9 +22,10 @@ describe('opencode provider', () => {
       env: { A: '1' },
     });
 
-    expect(cli.runCli).toHaveBeenCalledWith(['/usr/local/bin/opencode', '-c', '/tmp/work', '-p', 'hello'], {
-      env: { A: '1' },
-    });
+    expect(cli.runCli).toHaveBeenCalledWith(
+      ['/usr/local/bin/opencode', 'run', '--dir', '/tmp/work', 'hello'],
+      { env: { A: '1' } },
+    );
     expect(result.isError).toBe(false);
     expect(result.result).toBe('final text');
     expect(result.metrics.numTurns).toBe(1);
@@ -68,10 +69,8 @@ describe('opencode provider', () => {
     const result = await provider.execute('hello', { model: 'openai/gpt-5' });
 
     expect(cli.runCli).toHaveBeenCalledWith(
-      ['opencode', '-p', 'hello'],
-      {
-        env: { MODEL: 'openai/gpt-5' },
-      }
+      ['opencode', 'run', '-m', 'openai/gpt-5', 'hello'],
+      { env: {} },
     );
     expect(result.isError).toBe(false);
   });