Per-channel configuration

One agent can run across phone, web chat, email, text, and SMS. Per-channel configuration lets you tune how that agent thinks and how its replies are rendered on each channel, without forking the agent. Both maps are optional and additive: when a channel has no entry it inherits the base agent config, so voice and web behaviour is unaffected. There are two independent maps, keyed by channel (telephone, webrtc, webchat, sms, email, text):

Map	Group	What it controls
`channel_overrides`	LLM steering	How the agent thinks and responds — instructions, greeting, tool budget.
`channel_properties`	Transport / presentation	How the reply is rendered and sent — body template, subject, signature, SMS segments, enabled flag.

channel_overrides and channel_properties live on a static_prompt agent config. They are consumed by the async messaging engine (SMS, email, text, and webchat — the text-only web widget). Voice and WebRTC ignore channel_properties transport mechanics and fall back to the base config.webrtc is the web widget with voice (a LiveKit session) and webchat is the web widget with its Text only toggle on. They are separate keys on purpose: text wants different steering than voice (markdown, no spoken-style phrasing, its own greeting, possibly a different model), and nothing configured under webrtc applies to webchat or the other way round.

channel_overrides

Each entry steers inference for one channel. Fields are merged with the base config at resolution time.

Field	Type	Default	Description
`instructions`	string	none	Extra prompt text for this channel.
`instructions_mode`	`append` \| `replace`	`append`	`append` joins this text after the base instructions; `replace` swaps them out entirely.
`starting_message`	starting message	none	Per-channel greeting. When set, it replaces the base greeting on this channel.
`max_tool_steps`	integer (≥ 1)	none	Per-channel tool-call budget per turn. When set, it overrides the base `max_tool_steps`.

When instructions_mode is append, the resolver concatenates base and override instructions separated by a blank line. If the base instructions are empty, the override is used as-is regardless of mode.

channel_properties

Each entry is a channel-exclusive block, discriminated by its channel field. Every block shares enabled (default true) and body_template (default {{agent_response}}), then adds channel-specific fields.

EmailProperties (`channel: "email"`)

Field	Type	Default	Description
`enabled`	boolean	`true`	Whether the agent responds on this channel.
`body_template`	string	`{{agent_response}}`	Template for the reply body.
`body_format`	`multipart` \| `html` \| `plaintext`	`multipart`	How the email body is rendered.
`subject_template`	string	`Re: {{subject}}`	Template for the reply subject line.
`default_subject`	string	none	Subject used when no inbound subject is available.
`from_display_name`	string	none	Display name shown on the `From` header.
`signature`	string	none	Signature appended to the body.
`template_wrapper`	string	none	Outer wrapper template applied around the body.
`include_unsubscribe_footer`	boolean	`true`	Append an unsubscribe footer.
`quote_history`	boolean	`false`	Quote the prior message thread under the reply.
`cc_reply_policy`	`conditional` \| `never` \| `always`	`conditional`	Whether to keep `Cc` recipients on replies. `conditional` keeps them only when appropriate.
`require_dmarc_pass`	boolean	`false`	Require inbound mail to pass DMARC before the agent replies.
`auto_close_on_conclusion`	boolean	`true`	Close the conversation when the exchange concludes.

For the full email-agent reference (domains, routing, and the fields above in context), see Configuring an email agent.

SmsProperties (`channel: "sms"`)

Field	Type	Default	Description
`enabled`	boolean	`true`	Whether the agent responds on this channel.
`body_template`	string	`{{agent_response}}`	Template for the message body.
`max_segments`	integer (≥ 1)	`3`	Maximum SMS segments per message.
`on_overflow`	`truncate` \| `split`	`truncate`	When the body exceeds `max_segments`, either cut it off or split it across messages.
`strip_markdown`	boolean	`true`	Remove markdown formatting before sending.
`allow_unicode`	boolean	`true`	Permit non-GSM Unicode characters.
`append_opt_out_footer`	boolean	`false`	Append an opt-out footer to outbound messages.

TextProperties (`channel: "text"`)

The first-party API text channel has no transport mechanics, so it carries only the shared fields.

Field	Type	Default	Description
`enabled`	boolean	`true`	Whether the agent responds on this channel.
`body_template`	string	`{{agent_response}}`	Template for the response body.

WebchatProperties (`channel: "webchat"`)

The text-only web widget. Like text it has no transport mechanics and no enabled flag: a published widget is the switch.

Field	Type	Default	Description
`body_template`	string	`{{agent_response}}`	Template for the response body.

A webchat conversation is answered by the async engine, so channel_overrides.webchat (instructions, greeting, tool budget, LLM override) applies to it, and the agent’s widgets, forms, thinking hint and continue_on_phone tools are offered exactly as on the LiveKit widget. An escalation (a handoff action) can carry a channels.webchat route, set under Route by channel in the action.

How resolution works

When a message arrives on a channel, resolve_channel_config folds the base agent config with that channel’s override and property blocks into a single effective config:

base config ──┐
              ├── instructions  = base, base+"\n\n"+override (append), or override (replace)
override  ────┤── starting_message = override if set, else base
              ├── max_tool_steps = override if set, else base, else 3 (default)
properties ───┴── enabled / body_template = from channel_properties, else defaults
                  properties = the matching email/sms/text block (or none)

The resolved values:

Resolved field	Source order
`instructions`	base, or base + override (append), or override (replace)
`starting_message`	channel override, else base
`max_tool_steps`	channel override, else base, else `3`
`enabled`	`channel_properties.enabled`, else `true`
`body_template`	`channel_properties.body_template`, else `{{agent_response}}`
`properties`	the matching channel-properties block, else none

If a channel has no override and no properties entry, the base config is returned unchanged. This keeps voice and WebRTC untouched when you add async-channel tuning.

Getting Started

Agents

Knowledge Bases

Telephony

Web Widgets

Email

Campaigns

Conversations

Evaluation & Metrics

Agent Assist

Workflows

Organizing Agents & Workflows

Custom Data

Anyreach over MCP

Organizations & Billing

Per-channel configuration

channel_overrides

channel_properties

EmailProperties (`channel: "email"`)

SmsProperties (`channel: "sms"`)

TextProperties (`channel: "text"`)

WebchatProperties (`channel: "webchat"`)

How resolution works

Next steps

Configuring an email agent

Channels

​channel_overrides

​channel_properties

​EmailProperties (channel: "email")

​SmsProperties (channel: "sms")

​TextProperties (channel: "text")

​WebchatProperties (channel: "webchat")

​How resolution works

​Next steps

Configuring an email agent

Channels

channel_overrides

channel_properties

EmailProperties (`channel: "email"`)

SmsProperties (`channel: "sms"`)

TextProperties (`channel: "text"`)

WebchatProperties (`channel: "webchat"`)

How resolution works

Next steps