Agent Profiles and the Agent Editor

Agent Profiles give a chat a repeatable role, set of instructions, model preset, and capability policy. Use one when you want Agent Zero to work consistently as a developer, researcher, reviewer, writer, or another specialist.

The Agent Editor is deterministic: it does not call a model to interpret your changes. It writes only the profile overrides shown in its Review page and leaves the bundled profiles under /a0/agents unchanged.

Open the Agent Editor

The profile menu is beside the chat input.

• Select a profile name to use it in the current chat.
• Select Edit on a row to open that profile in Easy mode.
• Select Manage agents to create, duplicate, reset, delete, or change the availability of profiles.

Changing the selected profile affects only that chat. To choose the profile for future Global chats, open Settings -> Agent Config.

Create or edit a profile in Easy mode

Open Manage agents, select Create agent, and complete the form:

1. Choose Global to make the profile available everywhere, or choose a project to keep the profile and its overrides in that project.
2. Enter the agent name. Agent Zero creates a stable profile ID from the name.
3. Optionally choose a color or image.
4. Select a model preset, or keep the current preset.
5. Write direct instructions: what the agent should do, how it should reason, and how it should communicate.
6. Review the capability defaults and any individual Tool, MCP, or Skill decisions.
7. Select Create agent or Save changes.

Creating a profile opens a fresh chat with the new profile selected. Editing an existing profile also offers Save & test, which saves and opens a fresh chat for testing without changing the old chat's history.

Choose capability access

Easy mode has separate default switches and expandable lists for Tools, MCPs, and Skills.

Each item has three states:

Changing a category default affects current and future items that remain on Default. Explicit On and Off decisions stay pinned. Tools and MCPs have separate defaults even though their decisions are stored by the same Tool Access policy owner. Skills use their own visibility policy.

[!NOTE] Skill access controls discovery and new loading. It does not remove skill text that is already part of a chat's saved history.

Manage existing profiles and project availability

Manage agents shows the active profile and every profile available to the selected scope. Use the Project selector before making a change.

The row actions have distinct effects:

To stop a profile from being selected or delegated to in one project:

1. Open Manage agents.
2. Choose the project.
3. Turn that profile's availability toggle off.

The Global profile is not deleted or changed. Agent Zero keeps at least one profile available in every scope; if a chat uses a profile that becomes unavailable, it is reconciled to an available profile.

Advanced mode

Select Advanced when you need more than the Easy form. The left navigation separates six concerns:

1. Identity — title, description, profile ID, delegation guidance, image, and model preset.
2. Prompt files — edit individual inherited or customized Markdown prompt files in the ACE editor.
3. Tools — search local and plugin tools and set their access policy.
4. MCPs — set access independently for tools discovered from MCP servers.
5. Skills — control which installed skills the profile can discover and load.
6. Review — inspect the exact files that will be created, updated, or deleted before saving.

Edit prompt files

Choose a prompt file on the left. The editor shows its effective source and the sparse customization path. Reset to default removes only your override for that file.

Review explicit capability decisions

Advanced Tools, MCPs, and Skills use the same On / Default / Off semantics as Easy mode, with search and origin filtering. Advanced mode can also show a retained decision for an item that is not currently available, so you can clear or change stale configuration.

Review before saving

Review is the source of truth for the save. If a file is not listed, the editor will not write or delete it.

For a built-in profile, Remove my changes deletes only the selected scope's overrides. Full deletion is offered only for custom profiles.

Use profiles from A0 CLI

The A0 CLI Connector exposes the same profile and permission owners.

/profile
/profile Developer
/profile "Source Scout" "Verify every important claim and cite the source."
/permissions

• /profile opens the profile menu. Choose Create profile or Edit current profile for a compact two-step editor.
• /profile Developer selects an existing profile by name or ID.
• /profile "<name>" "<instructions>" creates a profile in the current chat's Global or project scope, then opens a fresh chat with it selected.
• /permissions edits Tools, MCPs, and Skills for the current profile. Each row cycles through Default, On, and Off; Tools and MCPs have independent defaults.

The CLI derives scope from the current chat. It intentionally has no separate scope selector: a project chat edits that project, while a chat with no project edits Global.

Power-user file overrides

Prefer the Agent Editor because it validates changes and shows the exact save plan. If you manage files directly, use the same sparse layout and formats.

Never edit the bundled /a0/agents/<profile-id> files for a customization. Create only the files and keys you need to override.

<profile-root>/
├── agent.yaml
├── prompts/
│   └── agent.system.main.specifics.md
└── plugins/
    ├── _model_config/config.json
    ├── _tool_access/config.json
    └── _skills/config.json

Identity definition: YAML

Authored profile definitions use YAML. A missing key inherits; an explicitly empty value clears that field.

title: Source Scout
description: Researches technical claims and returns concise evidence.
context: Use this agent for source discovery and claim verification.

Prompt overrides: Markdown

Place a Markdown file under prompts/ with the same filename as the prompt you want to replace. Do not copy the whole prompt tree. For example:

prompts/agent.system.main.specifics.md

The Agent Editor's Prompt files page is the easiest way to discover available filenames and the exact customization path. See the Prompts guide for the prompt-loading model.

Tool and MCP policy: JSON

Runtime and editor-written configuration uses JSON. Tools and MCPs share plugins/_tool_access/config.json, but have independent defaults:

{
  "mode": "custom",
  "default": "allow",
  "mcp_default": "block",
  "allowed": [
    "local:call_subordinate",
    "mcp:deep_wiki:ask_question"
  ],
  "blocked": [
    "plugin:_code_execution:code_execution_tool"
  ]
}

Canonical IDs use these forms:

An ID in allowed is On; an ID in blocked is Off; an ID in neither list follows default or mcp_default. Runtime-required response handling is not offered as a configurable tool.

MCP server definitions themselves still belong in Settings -> MCP. The profile policy decides which discovered MCP tools the agent may use; it does not create or connect an MCP server. See MCP Setup.

Skill visibility policy: JSON

Skills use plugins/_skills/config.json. Keep the policy inside visibility_policy so unrelated Skills settings remain intact:

{
  "visibility_policy": {
    "mode": "custom",
    "default": "allow",
    "allowed": ["Research"],
    "blocked": ["Deploy production"]
  }
}

The entries are skill names or paths recognized by the Skills catalog. See the Skills guide for writing and installing skill definitions.

Model preset selection: JSON

To pin a profile to an existing preset, use plugins/_model_config/config.json:

{
  "model_preset": "Codex"
}

Use Edit Presets in the UI to author presets; profile configuration should only select one. See Model Presets.

Profile, Skill, Project, or model preset?

For small local models that narrate instead of calling tools, use the bundled Tiny Local profile or the project-scoped Prompt Include recipe in Local Model Tool Use.

For source-linked internals, use DeepWiki for Agent Zero.