> ## Documentation Index > Fetch the complete documentation index at: https://docs.enginy.ai/llms.txt > Use this file to discover all available pages before exploring further. # Validate campaign > Validate a simplified public campaign payload against the public step schema without creating a campaign. Use this before `POST /v1/campaigns` when you already have a proposed request body. This validates only the submitted payload and does not read or inspect an existing saved campaign. This endpoint validates only the submitted request body. It does not load, inspect, or verify an already-saved campaign in Enginy. Create a draft campaign from the public `steps` format. How to structure the request: - Start `steps` with the first action that should happen. - Keep adding the next action in the order it should run. - Use `condition` when you want to branch on lead data. - Use `linkedin_connection` with `waitForAcceptance` when you want to branch on connection acceptance after sending a connection request. Omit `waitForAcceptance` for a fire-and-forget connection request. - Use `linkedin_message` with `content`, `attachment`, or both. Attachment-only messages are valid. - Use `whatsapp_message` only when the workspace and sending identity are configured for WhatsApp. - Put shared follow-up work after the branching step instead of duplicating the same steps inside both branches. Before you send a request: - Send an ordered `steps` array that describes the campaign flow from first action to last action. - Use branch arrays on `condition` and `linkedin_connection` steps to describe branch-specific work. - Place shared follow-up steps after a branching step when both live branches should continue together. - `waitForAcceptance.unit` must be `days` and `waitForAcceptance.value` must be an integer greater than or equal to `1`. - Use `GET /v1/tasks/owners` first when your campaign includes `task` steps. If owners are returned, every `task` step must include `ownerId`. - Validation errors use full paths like `steps[0].onTrue[1].subject` so nested input issues are easy to fix. - Personalization placeholders use Enginy single-brace syntax such as `{firstName}`, `{company}`, and `{identity.name}`. Do not send Handlebars-style placeholders like `{{firstName}}`. Supported `condition.type` values: - `has_linkedin_profile`: `onTrue` runs when the lead has a LinkedIn profile. - `has_professional_email`: `onTrue` runs when the lead has a professional email. - `is_already_connected`: `onTrue` runs when the lead is already a LinkedIn connection. - `has_been_contacted`: `onTrue` runs when the lead has already been contacted. - `has_whatsapp_account`: `onTrue` runs when the lead has a WhatsApp account. - `email_opened`: `onTrue` runs when the lead opens the preceding email within `waitFor`. Must follow an `email` step. Requires `waitFor` (`value`, `unit`). - `email_clicked`: `onTrue` runs when the lead clicks a link in the preceding email within `waitFor`. Must follow an `email` step. Requires `waitFor` (`value`, `unit`). - `task_completed`: `onTrue` runs when the preceding `task` step is marked complete within `waitFor`. Must follow a `task` step. Requires `waitFor` (`value`, `unit`). - `connection_accepted`: `onTrue` runs when the lead accepts a previous LinkedIn connection request within `waitFor`. Requires `waitFor` (`value`, `unit`). - `lead_field`: `onTrue` runs when the contact `field` matches the `operator` (and `value`, where applicable). Use this to branch on any built-in column or custom field. Requires `field` and `operator`. `value` is required for every operator except `IS_EMPTY` and `IS_NOT_EMPTY`. Supported operators: `EQUALS`, `NOT_EQUALS`, `CONTAINS`, `NOT_CONTAINS`, `GREATER_THAN`, `LESS_THAN`, `GREATER_THAN_OR_EQUALS`, `LESS_THAN_OR_EQUALS`, `IS_EMPTY`, `IS_NOT_EMPTY`. Branch fields: - `condition` uses `onTrue` and `onFalse`. - `linkedin_connection` uses `onAccepted` and `onNotAccepted` only when `waitForAcceptance` is set. - Use `[{ "type": "end" }]` when a branch should stop explicitly. Routing into another campaign: - Use `add_to_another_campaign` with a `campaignId` to route the lead into an existing campaign in the same workspace. - The referenced `campaignId` must belong to the same client as the API key. If you are cloning campaigns across workspaces, remap each `campaignId` to the equivalent campaign in the destination workspace before posting. - Can be followed by additional steps in the same branch. For examples and a full step-by-step guide, see `/api-reference/campaigns-guide` in the docs site. > **Required scope:** `CAMPAIGNS_WRITE` > > **Rate limit:** 30 requests per minute ## OpenAPI ````yaml https://openapi.enginy.ai/definitions.json post /v1/campaigns/validate openapi: 3.1.0 info: title: Enginy API version: 1.0.0 description: Public API for Enginy platform servers: - url: https://openapi.enginy.ai description: Configured server security: [] tags: - name: AI Variables description: >- Manage AI variables and discover the entity fields you can reference in prompts and entity requests. - name: Inbox description: >- Inbox endpoints for listing contact threads, reading thread messages, managing tags, and sending manual replies. - name: Workflows description: >- Build, validate, publish, run, and inspect advanced (graph) workflows, plus the block/condition catalog needed to author a workflow plan. paths: /v1/campaigns/validate: post: tags: - Campaigns summary: Validate campaign description: >- Validate a simplified public campaign payload against the public step schema without creating a campaign. Use this before `POST /v1/campaigns` when you already have a proposed request body. This validates only the submitted payload and does not read or inspect an existing saved campaign. This endpoint validates only the submitted request body. It does not load, inspect, or verify an already-saved campaign in Enginy. Create a draft campaign from the public `steps` format. How to structure the request: - Start `steps` with the first action that should happen. - Keep adding the next action in the order it should run. - Use `condition` when you want to branch on lead data. - Use `linkedin_connection` with `waitForAcceptance` when you want to branch on connection acceptance after sending a connection request. Omit `waitForAcceptance` for a fire-and-forget connection request. - Use `linkedin_message` with `content`, `attachment`, or both. Attachment-only messages are valid. - Use `whatsapp_message` only when the workspace and sending identity are configured for WhatsApp. - Put shared follow-up work after the branching step instead of duplicating the same steps inside both branches. Before you send a request: - Send an ordered `steps` array that describes the campaign flow from first action to last action. - Use branch arrays on `condition` and `linkedin_connection` steps to describe branch-specific work. - Place shared follow-up steps after a branching step when both live branches should continue together. - `waitForAcceptance.unit` must be `days` and `waitForAcceptance.value` must be an integer greater than or equal to `1`. - Use `GET /v1/tasks/owners` first when your campaign includes `task` steps. If owners are returned, every `task` step must include `ownerId`. - Validation errors use full paths like `steps[0].onTrue[1].subject` so nested input issues are easy to fix. - Personalization placeholders use Enginy single-brace syntax such as `{firstName}`, `{company}`, and `{identity.name}`. Do not send Handlebars-style placeholders like `{{firstName}}`. Supported `condition.type` values: - `has_linkedin_profile`: `onTrue` runs when the lead has a LinkedIn profile. - `has_professional_email`: `onTrue` runs when the lead has a professional email. - `is_already_connected`: `onTrue` runs when the lead is already a LinkedIn connection. - `has_been_contacted`: `onTrue` runs when the lead has already been contacted. - `has_whatsapp_account`: `onTrue` runs when the lead has a WhatsApp account. - `email_opened`: `onTrue` runs when the lead opens the preceding email within `waitFor`. Must follow an `email` step. Requires `waitFor` (`value`, `unit`). - `email_clicked`: `onTrue` runs when the lead clicks a link in the preceding email within `waitFor`. Must follow an `email` step. Requires `waitFor` (`value`, `unit`). - `task_completed`: `onTrue` runs when the preceding `task` step is marked complete within `waitFor`. Must follow a `task` step. Requires `waitFor` (`value`, `unit`). - `connection_accepted`: `onTrue` runs when the lead accepts a previous LinkedIn connection request within `waitFor`. Requires `waitFor` (`value`, `unit`). - `lead_field`: `onTrue` runs when the contact `field` matches the `operator` (and `value`, where applicable). Use this to branch on any built-in column or custom field. Requires `field` and `operator`. `value` is required for every operator except `IS_EMPTY` and `IS_NOT_EMPTY`. Supported operators: `EQUALS`, `NOT_EQUALS`, `CONTAINS`, `NOT_CONTAINS`, `GREATER_THAN`, `LESS_THAN`, `GREATER_THAN_OR_EQUALS`, `LESS_THAN_OR_EQUALS`, `IS_EMPTY`, `IS_NOT_EMPTY`. Branch fields: - `condition` uses `onTrue` and `onFalse`. - `linkedin_connection` uses `onAccepted` and `onNotAccepted` only when `waitForAcceptance` is set. - Use `[{ "type": "end" }]` when a branch should stop explicitly. Routing into another campaign: - Use `add_to_another_campaign` with a `campaignId` to route the lead into an existing campaign in the same workspace. - The referenced `campaignId` must belong to the same client as the API key. If you are cloning campaigns across workspaces, remap each `campaignId` to the equivalent campaign in the destination workspace before posting. - Can be followed by additional steps in the same branch. For examples and a full step-by-step guide, see `/api-reference/campaigns-guide` in the docs site. > **Required scope:** `CAMPAIGNS_WRITE` > > **Rate limit:** 30 requests per minute requestBody: content: application/json: schema: type: object properties: name: type: string minLength: 1 description: Campaign name. description: type: - string - 'null' description: Optional campaign description. identityId: type: - integer - 'null' exclusiveMinimum: 0 shouldAutomaticallySend: type: boolean shouldSendTrackingPixel: type: boolean shouldTrackEmailLinks: type: boolean excludeContactedLeads: type: boolean allowedEmails: type: array items: type: string description: Allowed sender email addresses for this campaign. steps: type: array items: oneOf: - type: object properties: type: type: string enum: - email subject: type: string minLength: 1 content: type: string minLength: 1 delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type - subject - content additionalProperties: false title: email - type: object properties: type: type: string enum: - linkedin_message content: type: string minLength: 1 description: >- LinkedIn message body. Required unless `attachment` is provided. attachment: type: string minLength: 1 description: >- Optional URL or storage key of the file to send alongside the message. attachmentName: type: string minLength: 1 description: Optional display name for the attachment. contentType: type: string enum: - AUDIO - IMAGE - FILE - VIDEO description: >- Attachment kind. Recommended when `attachment` is set. Use `VIDEO` for video files. delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type additionalProperties: false title: linkedin_message - type: object properties: type: type: string enum: - linkedin_message_bundle messages: type: array items: type: object properties: content: type: string minLength: 1 description: Text body of the bundle message. attachment: type: string minLength: 1 description: URL or storage key of the file to send. attachmentName: type: string minLength: 1 description: Display name for the attachment. contentType: type: string enum: - AUDIO - IMAGE - FILE - VIDEO description: >- Attachment kind. Recommended when `attachment` is set. Use `VIDEO` for video files. additionalProperties: false minItems: 1 description: >- Ordered list of messages sent back-to-back as a single bundle. delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type - messages additionalProperties: false title: linkedin_message_bundle - type: object properties: type: type: string enum: - linkedin_voice_message content: type: string minLength: 1 description: >- Text body that will be synthesized to speech via the configured `voiceId`. voiceId: type: string minLength: 1 description: >- ID of a system voice or an identity-cloned voice. Use `GET /v1/voices` to list valid voice IDs. attachment: type: string minLength: 1 description: >- URL or storage key for a pre-recorded audio message. attachmentName: type: string minLength: 1 description: Optional display name for the audio file. contentType: type: string enum: - AUDIO description: Set to `AUDIO` when `attachment` is provided. voiceSettings: type: object properties: voiceSpeed: type: number minimum: 0.5 maximum: 2 description: >- Speech rate multiplier. Range 0.5–2.0. Defaults are applied server-side when omitted. voiceStability: type: number minimum: 0 maximum: 100 description: >- Voice stability percentage (0–100). Higher is steadier, lower is more expressive. backgroundNoise: type: string minLength: 1 description: >- Optional background noise preset (e.g. `none`, `office`). Server defaults to `none`. backgroundVolume: type: number minimum: 0 maximum: 100 description: >- Background noise volume (0–100). Ignored when `backgroundNoise` is `none`. additionalProperties: false description: >- Optional fine-tuning of the synthesized voice and background audio. delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type additionalProperties: false title: linkedin_voice_message - type: object properties: type: type: string enum: - linkedin_inmail subject: type: string minLength: 1 content: type: string minLength: 1 delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type - subject - content additionalProperties: false title: linkedin_inmail - type: object properties: type: type: string enum: - linkedin_visit_profile delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type additionalProperties: false title: linkedin_visit_profile - type: object properties: type: type: string enum: - linkedin_like_last_post delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false reactionType: type: string minLength: 1 required: - type additionalProperties: false title: linkedin_like_last_post - type: object properties: type: type: string enum: - whatsapp_message content: type: string minLength: 1 description: >- WhatsApp message body. Requires WhatsApp support on the workspace and identity. delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type - content additionalProperties: false title: whatsapp_message - type: object properties: type: type: string enum: - condition condition: oneOf: - type: object properties: type: type: string enum: - has_linkedin_profile description: Lead has a LinkedIn profile. field: type: string enum: - linkedinProfileUrl - linkedInProfileId description: >- Stored lead field to check. Defaults to `linkedinProfileUrl`. required: - type additionalProperties: false title: has_linkedin_profile - type: object properties: type: type: string enum: - has_professional_email description: Lead has a professional email. verificationStatuses: type: array items: type: string description: >- Optional email verification statuses to include when matching. includeEmpty: type: boolean description: >- Whether empty professional email values match. required: - type additionalProperties: false title: has_professional_email - type: object properties: type: type: string enum: - is_already_connected description: Lead is already a LinkedIn connection. required: - type additionalProperties: false title: is_already_connected - type: object properties: type: type: string enum: - has_been_contacted description: Lead has already been contacted. required: - type additionalProperties: false title: has_been_contacted - type: object properties: type: type: string enum: - has_whatsapp_account description: Lead has a WhatsApp account. required: - type additionalProperties: false title: has_whatsapp_account - type: object properties: type: type: string enum: - email_opened description: >- Branch on whether the preceding email is opened within `waitFor`. waitFor: type: object properties: value: type: number exclusiveMinimum: 0 description: Wait amount. unit: type: string enum: - seconds - minutes - hours - days description: Wait unit. required: - value - unit additionalProperties: false description: >- How long to wait for the lead to open the preceding email. Required. required: - type - waitFor additionalProperties: false title: email_opened - type: object properties: type: type: string enum: - email_clicked description: >- Branch on whether a link in the preceding email is clicked within `waitFor`. waitFor: type: object properties: value: type: number exclusiveMinimum: 0 description: Wait amount. unit: type: string enum: - seconds - minutes - hours - days description: Wait unit. required: - value - unit additionalProperties: false description: >- How long to wait for the lead to click a link in the preceding email. Required. required: - type - waitFor additionalProperties: false title: email_clicked - type: object properties: type: type: string enum: - task_completed description: >- Branch on whether the preceding task is marked complete within `waitFor`. waitFor: type: object properties: value: type: number exclusiveMinimum: 0 description: Wait amount. unit: type: string enum: - seconds - minutes - hours - days description: Wait unit. required: - value - unit additionalProperties: false description: >- How long to wait for the task to be marked complete. Required. required: - type - waitFor additionalProperties: false title: task_completed - type: object properties: type: type: string enum: - connection_accepted description: >- Branch on whether the lead accepts a previous LinkedIn connection request. waitFor: type: object properties: value: type: number exclusiveMinimum: 0 description: Wait amount. unit: type: string enum: - seconds - minutes - hours - days description: Wait unit. required: - value - unit additionalProperties: false description: >- How long to wait for the lead to accept the previous LinkedIn connection request. Required. required: - type - waitFor additionalProperties: false title: connection_accepted - type: object properties: type: type: string enum: - lead_field description: Branch on a lead field value. field: type: string minLength: 1 description: >- Built-in column name (e.g. `professionalEmail`, `mobilePhone`) or custom field name. operator: type: string enum: - EQUALS - NOT_EQUALS - CONTAINS - NOT_CONTAINS - GREATER_THAN - LESS_THAN - GREATER_THAN_OR_EQUALS - LESS_THAN_OR_EQUALS - IS_EMPTY - IS_NOT_EMPTY description: >- Comparison operator. `IS_EMPTY` and `IS_NOT_EMPTY` ignore `value`; all others require it. value: anyOf: - type: string - type: number - type: boolean - type: array items: type: string - type: array items: type: number - type: array items: type: boolean description: >- Comparison value. Required for every operator except `IS_EMPTY` and `IS_NOT_EMPTY`. required: - type - field - operator additionalProperties: false title: lead_field description: >- Condition evaluated at this point in the sequence. Supported `condition.type` values are `has_linkedin_profile`, `has_professional_email`, `is_already_connected`, `has_been_contacted`, `has_whatsapp_account`, `email_opened`, `email_clicked`, `task_completed`, `connection_accepted`, and `lead_field`. The email, task, and connection-accepted variants require a `waitFor` object with `value` and `unit`. The `lead_field` variant requires `field` and `operator`, and a `value` for every operator except `IS_EMPTY` and `IS_NOT_EMPTY`. onTrue: type: array items: type: object properties: type: type: string description: Nested branch step type. required: - type additionalProperties: {} description: >- Nested branch step. Use the same step payload shape as top-level `steps` items. minItems: 1 description: >- Steps to run when the condition matches. If provided, it must contain at least one step. Use `{ "type": "end" }` to stop that branch explicitly. onFalse: type: array items: type: object properties: type: type: string description: Nested branch step type. required: - type additionalProperties: {} description: >- Nested branch step. Use the same step payload shape as top-level `steps` items. minItems: 1 description: >- Steps to run when the condition does not match. If provided, it must contain at least one step. Use `{ "type": "end" }` to stop that branch explicitly. required: - type - condition additionalProperties: false title: condition - type: object properties: type: type: string enum: - linkedin_connection delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false content: type: string minLength: 1 waitForAcceptance: type: object properties: value: type: integer minimum: 1 description: whole number of days to wait. Minimum 1 day. unit: type: string enum: - days description: Connection wait unit. Must be `days`. required: - value - unit additionalProperties: false description: >- Optional. Provide an acceptance window to branch the flow on whether the lead accepted the request. Omit to send the request without an inline acceptance check; the campaign continues with whatever follows. onAccepted: type: array items: type: object properties: type: type: string description: Nested branch step type. required: - type additionalProperties: {} description: >- Nested branch step. Use the same step payload shape as top-level `steps` items. minItems: 1 description: >- Accepted branch steps. Only valid when `waitForAcceptance` is set. If provided, it must contain at least one step. Use `{ "type": "end" }` to stop that branch explicitly. onNotAccepted: type: array items: type: object properties: type: type: string description: Nested branch step type. required: - type additionalProperties: {} description: >- Nested branch step. Use the same step payload shape as top-level `steps` items. minItems: 1 description: >- Not-accepted branch steps. Only valid when `waitForAcceptance` is set. If provided, it must contain at least one step. Use `{ "type": "end" }` to stop that branch explicitly. required: - type additionalProperties: false title: linkedin_connection - type: object properties: type: type: string enum: - task taskType: type: string minLength: 1 description: >- Task type. Allowed values depend on the connected CRM. For HubSpot use one of: CALL, EMAIL, or TODO. Do not invent variants such as "COLD_CALL" — use the closest standard value (e.g. "CALL"). example: CALL title: type: string minLength: 1 description: Required task title shown in the UI. note: type: string minLength: 1 description: Optional task note shown in the UI. ownerId: type: - string - 'null' minLength: 1 description: >- Required when `GET /v1/tasks/owners` returns one or more owners. delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type - taskType - title additionalProperties: false title: task - type: object properties: type: type: string enum: - add_to_another_campaign description: >- Routes the lead into another campaign owned by the same workspace, then ends this branch. campaignId: type: integer exclusiveMinimum: 0 description: >- ID of a campaign owned by the same client as the API key making the request. delay: type: object properties: value: type: number minimum: 0 description: Delay amount. unit: type: string enum: - seconds - minutes - hours - days description: Delay unit. required: - value - unit additionalProperties: false required: - type - campaignId additionalProperties: false title: add_to_another_campaign - type: object properties: type: type: string enum: - end required: - type additionalProperties: false title: end minItems: 1 description: >- Ordered campaign steps. Use branch arrays like `onTrue`, `onFalse`, `onAccepted`, and `onNotAccepted` for branching. required: - name - steps additionalProperties: false examples: conditionFirst: summary: Start with a condition and run different work on each branch value: name: Email or fallback task identityId: 323 steps: - type: condition condition: type: has_professional_email onTrue: - type: email subject: Great to connect content: Sharing a quick overview. onFalse: - type: task taskType: TODO title: Find email first ownerId: owner-1 linkedinAcceptance: summary: >- Branch on LinkedIn connection acceptance and continue after the branch value: name: LinkedIn acceptance flow identityId: 323 steps: - type: linkedin_connection delay: value: 1 unit: days waitForAcceptance: value: 5 unit: days onAccepted: - type: linkedin_message content: Thanks for accepting. delay: value: 2 unit: hours onNotAccepted: - type: task taskType: TODO title: Review no-response path ownerId: owner-1 - type: email subject: Following up content: Continuing after the LinkedIn decision. delay: value: 1 unit: days voiceMessageWithVideoFollowup: summary: LinkedIn voice message followed by a video message value: name: Voice + video outreach identityId: 323 steps: - type: linkedin_voice_message content: >- Hey {firstName}, sharing a quick voice intro about {company}. voiceId: bIHbv24MWmeRgasZH58o voiceSettings: voiceSpeed: 1 voiceStability: 80 backgroundNoise: none backgroundVolume: 25 - type: linkedin_message content: Following up with the demo video. attachment: https://example.com/uploads/demo.mp4 attachmentName: demo.mp4 contentType: VIDEO delay: value: 1 unit: days taskRoutingFallbacks: summary: Route multiple fallback branches into different task owners value: name: Task routing fallback flow identityId: 323 steps: - type: condition condition: type: has_professional_email onTrue: - type: email subject: Initial outreach content: Opening with email when contact data is ready. - type: linkedin_connection waitForAcceptance: value: 4 unit: days onAccepted: - type: task taskType: CALL title: Call after positive signal note: >- They accepted the connection and saw the first email. ownerId: owner-1 delay: value: 1 unit: days onNotAccepted: - type: task taskType: TODO title: Review cold branch manually ownerId: owner-2 onFalse: - type: task taskType: TODO title: Find email before launching sequence ownerId: owner-3 responses: '200': description: Campaign payload is valid against the public simplified schema content: application/json: schema: type: object properties: status: type: string enum: - success message: type: string data: type: object properties: isValid: type: boolean enum: - true description: Always true for successful validation responses. warnings: type: array items: type: string description: >- Non-blocking sequence warnings returned by shared campaign validation. required: - isValid - warnings required: - status - message - data '400': description: >- Bad request - the campaign payload does not match the public simplified schema. Common causes: - Referenced identity (`identityId`) does not exist in this workspace. - Unrecognized field on a step or branch (e.g. `delay` is not a valid key on conditional `onAccepted`/`onTrue`/`onFalse` branches — use a dedicated wait/delay node inside the branch instead). - Required field missing (the response `errors[].path` indicates which body location failed validation). '422': description: >- Unprocessable entity - the campaign steps are structurally invalid. Common causes the agent should fix before retrying: - EMAIL_OPENED / NOT_EMAIL_OPENED conditions may only appear *after* an EMAIL node in the same branch. Add the EMAIL node first or remove the condition. - Every conditional branch (`onAccepted`/`onNotAccepted`/`onTrue`/`onFalse`) must contain at least one node. Use `[{ "type": "end" }]` to terminate a branch explicitly instead of leaving it empty. - Templated fields (e.g. `{firstName}`, `{companyName}`) must reference AI variables or standard fields that exist for the campaign's entity. Use GET /v1/contacts/fields or GET /v1/companies/fields to discover valid placeholders before composing message bodies. - Reply emails inside the same thread may omit `subject`, but the first email in any thread must have a non-empty subject. security: - apiKey: [] components: securitySchemes: apiKey: type: apiKey in: header name: x-api-key ````