# PostalForm MPP Order Validate > PostalForm MPP Order Validate is a free API for AI agents from PostalForm at postalform.com, Free, status unknown (last checked 2026-10-11, last successful call 2026-07-06). Validates an MPP machine print-and-mail order and returns a price quote before payment and fulfillment ## Facts - Endpoint: POST https://postalform.com/api/machine/mpp/orders/validate?utm_source=zero.xyz - Price: Free - Status: unknown - Last checked: 2026-10-11 - Last successful call: 2026-07-06 - Success rate: 50% of calls made through Zero - Rating: 3.3 / 5 from 1 review - Activations on Zero: 6 - Provider: PostalForm - Docs: https://postalform.com/agents - Website: https://postalform.com - Tags: mail, print, letters, physical, postal, web - Canonical page: https://www.zero.xyz/c/postalform-validate-101cd1f7 - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uO3-O0rk-Mw7GeKFtZa7V Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability postalform-validate-101cd1f7 -d '' ``` Example prompt: Before I pay, validate my PostalForm letter order and give me a quote — it's a single-page color letter on standard mail class, sending from 123 Main St, Springfield IL 62701 to Jane Doe at 456 Elm Ave, Chicago IL 60601, using the PDF I uploaded. ## When to prefer this Use this endpoint when you need to validate a PostalForm MPP machine order and obtain a binding price quote before committing to payment and fulfillment. It is the required pre-flight step before placing a real postal order via PostalForm's agent-native API. Choose this over generic postal APIs when you need AI-agent-friendly structured quotes with certified mail options, bulk campaign validation, and postcard or letter mailpiece types. ## Known failure modes - Missing required fields (recipient name, sender/recipient address, content) returns a 400 validation error - Invalid address format or missing address fields returns a 400 error - Conflicting schema conditions (e.g. bulk PDF mode without pdf field) returns a 400 error - Unauthenticated or unpaid requests return 402 Payment Required with WWW-Authenticate challenge - Invalid PDF or unsupported content mode returns a 422 error - Network timeout returns a 5xx error ## How this service works Validate an MPP machine order and return a quote ## Output Returns a validated order object including a unique order ID, request ID, request hash, a detailed quote (price in USD, page count, billable page count, mail class, mailpiece type, color, double-sided, certified flags, and the upstream provider), validation status indicating whether this is a new or existing draft order, and a postcard guidelines URL if applicable. For bulk campaigns, also returns the recipient count and content mode. ## Request schema (JSON Schema) ```json { "type": "object", "allOf": [ { "if": { "required": [ "bulk" ], "properties": { "bulk": { "type": "object", "required": [ "content_mode" ], "properties": { "content_mode": { "const": "pdf" } } } } }, "then": { "required": [ "pdf" ], "properties": { "pdf": { "oneOf": [ { "type": "string", "minLength": 1, "description": "A data:application/pdf;base64,... URL or a public HTTPS download URL. The canonical format is the upload_token object variant." }, { "type": "object", "required": [ "upload_token" ], "properties": { "upload_token": { "type": "string", "minLength": 1, "description": "Preferred canonical PDF reference. Get this from PostalForm PDF upload tooling." } }, "additionalProperties": false }, { "type": "object", "required": [ "download_url", "file_id" ], "properties": { "file_id": { "type": "string", "minLength": 1, "description": "Stable file identifier paired with download_url." }, "download_url": { "type": "string", "format": "uri", "description": "HTTPS URL to a PDF file." } }, "additionalProperties": true } ] } } } } ], "oneOf": [ { "not": { "required": [ "bulk" ], "properties": { "bulk": { "type": "object", "allOf": [ { "oneOf": [ { "required": [ "csv_content" ] }, { "required": [ "recipients" ] } ] } ], "oneOf": [ { "type": "object", "required": [ "content_mode", "template_text" ], "properties": { "content_mode": { "const": "text" }, "template_text": { "type": "string", "minLength": 1, "description": "Required when bulk.content_mode is text. Use {{field_name}} merge tags from CSV headers or JSON recipient merge_fields and address fields. Plain text only: HTML tags are rejected because text mode would print them literally." } } }, { … (truncated) ``` ## Response schema (JSON Schema) ```json { "type": "object", "required": [ "request_id", "request_hash", "order_id", "status", "postcard_guidelines_url", "quote" ], "properties": { "bulk": { "anyOf": [ { "type": "object", "required": [ "recipient_count", "content_mode" ], "properties": { "content_mode": { "enum": [ "text", "html", "pdf" ], "type": "string" }, "recipient_count": { "type": "integer", "minimum": 1 } }, "additionalProperties": false }, { "type": "null" } ], "description": "Bulk campaign metadata when validating a bulk machine request. Null for single-recipient orders." }, "quote": { "type": "object", "required": [ "price_usd", "full_price_usd", "currency", "page_count", "billable_page_count", "double_sided", "color", "mail_class", "certified", "certified_return_receipt", "mailpiece_type", "postcard_size", "provider" ], "properties": { "color": { "type": "boolean" }, "currency": { "enum": [ "usd" ], "type": "string" }, "provider": { "type": "string" }, "certified": { "type": "boolean" }, "err_email": { "anyOf": [ { "type": "string", "format": "email" }, { "type": "null" } ] }, "price_usd": { "type": "number" }, "mail_class": { "enum": [ "standard", "priority", "express" ], "type": "string" }, "page_count": { "type": "integer", "minimum": 1 }, "double_sided": { "type": "boolean" }, "err_delivery": { "enum": [ "manual", "email" ], "type": "string" }, "postcard_size": { "anyOf": [ { "enum": [ "4x6", "6x9", "11x6" ], "type": "string" }, { "type": "null" } ] }, "full_price_usd": { "type": "number" }, "mailpiece_type": { "enum": [ "letter", "postcard" ], "type": "string" }, "signature_required": { "type": "boolean" }, "billable_page_count": { "type": "integer", "minimum": 1 }, "restricted_delivery": { "type": "boolean" }, "return_receipt_format": { "enum": [ "electronic", "physical" ], "type": " … (truncated) ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/postalform-validate-101cd1f7/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from postalform.com](https://www.zero.xyz/host/postalform.com/llms.txt)