Default Symphony concurrency to five workers

SPEC.md

@@ -410,7 +410,7 @@ Fields:
 Fields:
 
 - `max_concurrent_agents` (integer)
-  - Default: `10`
+  - Default: `5`
   - Changes SHOULD be re-applied at runtime and affect subsequent dispatch decisions.
 - `max_turns` (positive integer)
   - Default: `20`
@@ -583,7 +583,7 @@ not require recognizing or validating extension fields unless that extension is
 - `hooks.after_run`: shell script or null
 - `hooks.before_remove`: shell script or null
 - `hooks.timeout_ms`: integer, default `60000`
-- `agent.max_concurrent_agents`: integer, default `10`
+- `agent.max_concurrent_agents`: integer, default `5`
 - `agent.max_turns`: integer, default `20`
 - `agent.max_retry_backoff_ms`: integer, default `300000` (5m)
 - `agent.max_concurrent_agents_by_state`: map of positive integers, default `{}`

elixir/WORKFLOW.md

@@ -27,7 +27,7 @@ hooks:
   before_remove: |
     cd elixir && mise exec -- mix workspace.before_remove
 agent:
-  max_concurrent_agents: 10
+  max_concurrent_agents: 5
   max_turns: 20
 codex:
   command: codex --config shell_environment_policy.inherit=all --config model_reasoning_effort=xhigh --model gpt-5.3-codex app-server

elixir/lib/symphony_elixir/config/schema.ex

@@ -129,7 +129,7 @@ defmodule SymphonyElixir.Config.Schema do
 
     @primary_key false
     embedded_schema do
-      field(:max_concurrent_agents, :integer, default: 10)
+      field(:max_concurrent_agents, :integer, default: 5)
       field(:max_turns, :integer, default: 20)
       field(:max_retry_backoff_ms, :integer, default: 300_000)
       field(:max_concurrent_agents_by_state, :map, default: %{})

elixir/lib/symphony_elixir/installer/workflow_profile.ex

@@ -68,7 +68,7 @@ defmodule SymphonyElixir.Installer.WorkflowProfile do
   defp apply_profile_defaults(plan, "symphony-dev") do
     plan
     |> put_default(:terminal_states, @default_terminal_states)
-    |> put_default(:agent_max_concurrent_agents, 10)
+    |> put_default(:agent_max_concurrent_agents, 5)
     |> put_default(:agent_max_turns, 20)
     |> put_default(:human_review_state, @default_human_review_state)
     |> put_default(:rework_state, @default_rework_state)
@@ -77,7 +77,7 @@ defmodule SymphonyElixir.Installer.WorkflowProfile do
 
   defp apply_profile_defaults(plan, _profile) do
     plan
-    |> put_default(:agent_max_concurrent_agents, 10)
+    |> put_default(:agent_max_concurrent_agents, 5)
     |> put_default(:agent_max_turns, 20)
   end
 

elixir/test/support/test_support.exs

@@ -199,7 +199,7 @@ defmodule SymphonyElixir.TestSupport do
           workspace_root: Path.join(System.tmp_dir!(), "symphony_workspaces"),
           worker_ssh_hosts: [],
           worker_max_concurrent_agents_per_host: nil,
-          max_concurrent_agents: 10,
+          max_concurrent_agents: 5,
           max_turns: 20,
           max_retry_backoff_ms: 300_000,
           max_concurrent_agents_by_state: %{},

elixir/test/symphony_elixir/installer_apply_test.exs

@@ -60,6 +60,7 @@ defmodule SymphonyElixir.InstallerApplyTest do
 
     assert workflow_artifact.content =~ "Forge provider: GitHub"
     assert workflow_artifact.content =~ "Validation command before handoff: mix test"
+    assert workflow_artifact.content =~ "max_concurrent_agents: 5"
     assert workflow_artifact.content =~ "networkAccess: true"
     assert workflow_artifact.content =~ "Progress SLA"
     assert workflow_artifact.content =~ "Create or refresh `## Codex Workpad` within 5 minutes"

elixir/test/symphony_elixir/workspace_and_config_test.exs

@@ -743,7 +743,7 @@ defmodule SymphonyElixir.WorkspaceAndConfigTest do
     assert config.tracker.project_slug == nil
     assert config.workspace.root == Path.join(System.tmp_dir!(), "symphony_workspaces")
     assert config.worker.max_concurrent_agents_per_host == nil
-    assert config.agent.max_concurrent_agents == 10
+    assert config.agent.max_concurrent_agents == 5
     assert config.codex.command == "codex app-server"
 
     assert config.codex.approval_policy == "never"