No Errands

API documentation

No Errands gives an agent three real-world abilities in the United States: print and mail letters and postcards, send faxes, and book appointments with local businesses. This page is the human version of the three connector briefs that agents read. All four describe the same v0 contracts.

If you only want to use this from Muse, you do not need this page. Start at Get your key instead.

The three connectors

Connector Brief MCP endpoint REST base
No Errands Mail /connectors/muse.md https://api.noerrands.com/c/mail/mcp https://api.noerrands.com/c/mail/v1
No Errands Fax /connectors/fax/muse.md https://api.noerrands.com/c/fax/mcp https://api.noerrands.com/c/fax/v1
No Errands Bookings /connectors/booking/muse.md https://api.noerrands.com/c/booking/mcp https://api.noerrands.com/c/booking/v1

They share one account, one API key, one credit balance, one error envelope and one authentication scheme. REST and MCP take the same request bodies and return the same response bodies, so pick whichever your client speaks.

Item Value
OpenAPI 3.1 documents https://api.noerrands.com/c/mail/openapi.json, https://api.noerrands.com/c/fax/openapi.json, https://api.noerrands.com/c/booking/openapi.json
Protected resource metadata (RFC 9728) https://api.noerrands.com/.well-known/oauth-protected-resource/c/mail/mcp, https://api.noerrands.com/.well-known/oauth-protected-resource/c/fax/mcp, https://api.noerrands.com/.well-known/oauth-protected-resource/c/booking/mcp
Health check https://api.noerrands.com/health
Agent index https://noerrands.com/llms.txt

Authentication

Every call carries your key as a bearer token:

Authorization: Bearer ne_live_your_key_here

Keys look like ne_live_ or ne_test_ followed by 32 characters. We store only a SHA-256 hash and the first 12 characters, so we cannot tell you your key if you lose it. Create a new one instead.

A key has one of two scopes:

Scope Can do
read Check addresses, estimate cost, read status, list mail and faxes, read balance, create top-up links, search providers, read availability
read,write Everything above, plus send letters, postcards and faxes, and create and cancel bookings

If the key is missing or wrong you get 401 plus a WWW-Authenticate: Bearer resource_metadata="..." header pointing at that connector's RFC 9728 document.

Getting a key

POST https://api.noerrands.com/v1/keys - no authentication, limited to 5 requests per hour per IP.

Request: { "email": "you@example.com", "scope": "read,write" }

Response 201:

{
  "account_id": "acc_...",
  "api_key": "ne_live_...",
  "scope": "read,write",
  "balance_cents": 0,
  "topup_url": "https://..."
}

The key page calls this endpoint for you. One key works for all three connectors. Email addresses are not verified in v0; treat the key, not the email, as the account identity.

Errors

Every error has the same envelope, whichever connector produced it:

{ "error": { "code": "invalid_request", "message": "..." } }
HTTP code Extra fields Meaning
400 invalid_request field when known Something in the request is wrong
401 unauthorized Key missing, unknown, or revoked
402 insufficient_credits required_cents, balance_cents, topup_url Not enough credits; nothing was sent
403 forbidden_scope A write call with a read-only key
404 not_found No such record on this account
409 idempotency_conflict Same idempotency_key, different body
429 rate_limited retry_after_seconds Slow down
502 provider_error An upstream provider failed; any charge was refunded

Idempotency

Put an idempotency_key (a string up to 128 characters) on every send and every booking. For 24 hours, a repeat of the same key with the same body returns the original response instead of acting again. The same key with a different body returns 409 idempotency_conflict. Use one key per human request, not per retry.

Mail

Types

type Address = {
  name: string;            // 1..40 chars, required for send, optional for verify
  company?: string;        // <= 40
  line1: string;           // <= 64
  line2?: string;          // <= 64
  city: string;
  state: string;           // 2-letter
  zip: string;             // 5 or 9 digits
  country?: "US";          // US only in v0
};

type MailStatus = "created" | "processing" | "in_transit" | "delivered" | "returned" | "failed" | "cancelled";

type MailRecord = {
  mail_id: string;                 // "ml_<id>"
  kind: "letter" | "postcard";
  status: MailStatus;
  to: Address;
  from: Address;
  created_at: string;              // ISO 8601
  expected_delivery_date?: string; // YYYY-MM-DD
  credits_charged_cents: number;
  tracking_url?: string;
};

Endpoints

MCP tool Scope Cost REST
verify_address read free POST /c/mail/v1/addresses/verify
estimate_cost read free POST /c/mail/v1/estimate
send_letter write charged POST /c/mail/v1/letters
send_postcard write charged POST /c/mail/v1/postcards
get_mail_status read free GET /c/mail/v1/mail/{mail_id}
list_sent_mail read free GET /c/mail/v1/mail?limit=&cursor=
get_balance read free GET /c/mail/v1/balance
create_topup_link read free POST /c/mail/v1/topups
no tool read free GET /c/mail/v1/me

The server validates, estimates, checks your balance, charges, then calls the print provider. If the provider fails after the charge, the credits are refunded and you get 502 provider_error.

Item Price
Letter, first page, black and white $2.49
Each additional page $0.25
Color surcharge, per letter $0.50
Certified mail surcharge $7.50
Postcard $1.49
Address check Free
Cost estimate Free

Fax

Types

type FaxStatus = "queued" | "sending" | "delivered" | "failed";

Endpoints

MCP tool Scope Cost REST
estimate_fax_cost read free POST /c/fax/v1/estimate
send_fax write charged POST /c/fax/v1/faxes
get_fax_status read free GET /c/fax/v1/faxes/{fax_id}
list_faxes read free GET /c/fax/v1/faxes?limit=&cursor=
get_balance read free GET /c/fax/v1/balance
create_topup_link read free POST /c/fax/v1/topups

If you supply body_markdown and the configured provider will not accept rendered HTML, the server returns 400 invalid_request with field: "body_markdown" and a message telling you to supply a pdf_url.

Page counts come from the provider when available. Otherwise the server estimates one page per 3,000 characters and trues up the charge when the provider reports the final count, recording the adjustment on the ledger.

Item Price
Fax, first page $1.49
Each additional fax page $0.49
Fax cost estimate Free

Bookings

Free for the person booking. No call in this connector deducts credits. Merchants owe $1.00 per completed booking; see for businesses.

Endpoints

MCP tool Scope REST
search_providers read POST /c/booking/v1/providers/search
list_services read GET /c/booking/v1/providers/{provider_id}/services
get_availability read POST /c/booking/v1/providers/{provider_id}/availability
create_booking write POST /c/booking/v1/bookings
get_booking read GET /c/booking/v1/bookings/{booking_id}
cancel_booking write POST /c/booking/v1/bookings/{booking_id}/cancel
list_my_bookings read GET /c/booking/v1/bookings?limit=&cursor=

Merchant endpoints

These are for business owners in a browser, not for agents:

Test it with curl

Set your key once:

export API_KEY="ne_live_your_key_here"
export MAIL="https://api.noerrands.com/c/mail/v1"
export FAX="https://api.noerrands.com/c/fax/v1"
export BOOKING="https://api.noerrands.com/c/booking/v1"

Is the service up?

curl -s https://api.noerrands.com/health

Check the account and the balance:

curl -s "$MAIL/me" -H "Authorization: Bearer $API_KEY"
curl -s "$MAIL/balance" -H "Authorization: Bearer $API_KEY"

Check a postal address (free):

curl -s "$MAIL/addresses/verify" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"address":{"name":"Ada Lovelace","line1":"1 Main St","city":"Austin","state":"TX","zip":"78701"}}'

Get a price (free):

curl -s "$MAIL/estimate" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"kind":"letter","pages":2,"color":false,"certified":false}'

curl -s "$FAX/estimate" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"pages":3}'

Send a letter (this costs money):

curl -s "$MAIL/letters" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to":{"name":"Ada Lovelace","line1":"1 Main St","city":"Austin","state":"TX","zip":"78701"},
    "from":{"name":"Grace Hopper","line1":"2 Oak Ave","city":"Denver","state":"CO","zip":"80202"},
    "subject":"Hello",
    "body_markdown":"Dear Ada,\n\nThank you.\n\nGrace",
    "idempotency_key":"letter-to-ada-2026-09-21"
  }'

Send a postcard (this costs money):

curl -s "$MAIL/postcards" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to":{"name":"Ada Lovelace","line1":"1 Main St","city":"Austin","state":"TX","zip":"78701"},
    "from":{"name":"Grace Hopper","line1":"2 Oak Ave","city":"Denver","state":"CO","zip":"80202"},
    "front":{"text":"Greetings from Denver"},
    "message":"Wish you were here.",
    "idempotency_key":"postcard-to-ada-2026-09-21"
  }'

Send a fax (this costs money):

curl -s "$FAX/faxes" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "to_number":"+14155550123",
    "recipient_name":"Records Office",
    "pdf_url":"https://example.com/intake-form.pdf",
    "cover_note":"Intake form for Ada Lovelace.",
    "idempotency_key":"fax-to-records-2026-09-21"
  }'

Find a business and see its open slots (free):

curl -s "$BOOKING/providers/search" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"query":"haircut","city":"Austin","state":"TX","limit":5}'

curl -s "$BOOKING/providers/prv_01H8X/services" -H "Authorization: Bearer $API_KEY"

curl -s "$BOOKING/providers/prv_01H8X/availability" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"service_id":"svc_01","date_from":"2026-09-24","date_to":"2026-09-26"}'

Book it (free, but it puts a real person in a real calendar):

curl -s "$BOOKING/bookings" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "provider_id":"prv_01H8X",
    "service_id":"svc_01",
    "start_at":"2026-09-24T14:00:00-05:00",
    "customer":{"given_name":"Ada","family_name":"Lovelace","email":"ada@example.com","phone":"+14155550123"},
    "idempotency_key":"haircut-2026-09-24"
  }'

Check on things:

curl -s "$MAIL/mail/ml_01H8X" -H "Authorization: Bearer $API_KEY"
curl -s "$FAX/faxes/fx_01H8X" -H "Authorization: Bearer $API_KEY"
curl -s "$BOOKING/bookings?limit=5" -H "Authorization: Bearer $API_KEY"

Add credits:

curl -s "$MAIL/topups" \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"amount_cents":1000}'

On Windows PowerShell, use Invoke-RestMethod or wrap the JSON in single quotes with curl.exe rather than the curl alias.

Known gaps in v0

Support

Email support@noerrands.com.