{"uid":"cap_PO6fDzGta017DbpGnM82y","slug":"mailpulse-letter-status-tracking-198f12de","name":"MailPulse Letter Status & Tracking","description":"Check the status and tracking of a physical letter previously sent via POST /api/letters. Returns render status, expected delivery date, and (for certified mail) the USPS tracking number.","url":"https://mailpulse.theaslangroupllc.com/api/letters/ltr_6efe036558965c36?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object","properties":{}},"type":{"type":"string","const":"http"},"method":{"enum":["POST","PUT","PATCH"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"errors":{"type":"object","description":"Documented error responses, keyed by HTTP status code","additionalProperties":{"type":"object","required":["description"],"properties":{"example":{"type":"object"},"description":{"type":"string"}}}},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_vEmw5QkF6oaz_MIdn55RP","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Check the render status, expected delivery date, and USPS tracking number of a previously sent physical letter by its letter ID.","exampleAgentPrompt":"What's the status of the physical letter I sent yesterday — the ID was ltr_6efe036558965c36? I want to know if it's been rendered, when it's expected to arrive, and if it was certified mail, give me the USPS tracking number.","exampleUseCases":[{"title":"Track certified mail delivery","prompt":"I sent a certified letter to my client last week with MailPulse — the ID is ltr_6efe036558965c36. Can you pull up the USPS tracking number and tell me when it's expected to be delivered?"},{"title":"Confirm letter rendering before deadline","prompt":"I need to verify that the legal notice I mailed out via MailPulse actually got processed and rendered successfully — the letter ID is ltr_6efe036558965c36. Can you check its status right now?"},{"title":"Monitor automated mailing pipeline","prompt":"Our agent sent out a batch of letters yesterday. Check the status on letter ltr_6efe036558965c36 — I need to know if it's been rendered and what the expected delivery date is so I can update our CRM."}],"resultDescription":"Returns the letter's current render status (e.g. rendered, failed), the expected delivery date, and for certified mail letters, the USPS tracking number. May also include additional letter metadata such as mail type and timestamps.","failureModes":["Letter ID not found — returns 404 if the ltr_* ID does not exist or belongs to a different account","Letter still processing — render status may be pending if recently submitted","Invalid letter ID format — malformed ltr_* ID returns a validation error","Authentication failure — missing or invalid x402 payment header returns 402"],"whenToPreferThis":"Use this endpoint after sending a physical letter via MailPulse's POST /api/letters endpoint when you need to confirm the letter was successfully rendered, retrieve the expected delivery date for scheduling or follow-up, or obtain the USPS tracking number for certified mail. Prefer this over generic USPS tracking lookups when the letter was sent through MailPulse, as it provides render status in addition to delivery tracking.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-11T12:37:17.158Z","isFirstParty":false,"canonicalSlug":"mailpulse-letter-status-tracking-318be170"}