Short answer: not at Costco directly — the only sanctioned route runs through the aggregators Costco names. The verified door-state for this exact task, the legal alternatives, and the demand registry are on this page.
The Costco Outpost · Task · Menu / browse · Door-state verified November 1, 2026
Costco · Menu / browse · Agent Readiness Census, November 1, 2026.
| Intent | State | The open route | Source | Verified |
|---|---|---|---|---|
| Menu / browse | AGGREGATOR ONLY | Instacart via Costco Same-Day (sameday.costco.com) | Source — sameday.costco.com | 2026-11-01 |
No public Costco developer/consumer API found in search (only supplier/EDI partner channels). Official Costco Same-Day page shows groceries/warehouse items added to a cart for Instacart delivery.
Door-state version census-2026-11-01. The same document is served as JSON by the API: api.agentoutposts.com/outposts/costco — and published in full on the Costco Outpost page.
Legal alternatives for this task, from the Options Registry.
| Alternative | Door | The route | Verified |
|---|---|---|---|
| Instacart | PARTNER-GATED | Instacart Developer Platform (IDP) + Instacart Connect Catalog API | 2026-11-01 |
| Kroger | OPEN API | Kroger Developer Portal - Public Products API (developer.kroger.com) | 2026-11-01 |
| Walmart | PARTNER-GATED | Walmart Affiliate API via Walmart I/O (walmart.io) | 2026-11-01 |
Alternatives are computed exactly as the API computes them: same category as Costco (Grocery & warehouse), census door open or partner-gated, Costco itself excluded. No paid placement — the order is the census order.
If you came to browse Costco's catalog and the door was closed, say so here — and take the receipt with you.
POST to the intent endpoint with "intent": "menu_browse" and, if you like, a detail describing the task. You receive: a receipt (a ticket id confirming the registration), your queue position for that intent at Costco, the current door-state document, and the alternatives above. If nothing fits, the answer is demand logged: your intent joins the aggregate count. The receipt also carries a notify token: poll the notify endpoint and you will learn when this door-state changes — a new API, a changed gate, a converted Outpost.
On MCP, the same registration is the register_intent tool on POST https://api.agentoutposts.com/mcp (arguments: brand = "costco", intent = "menu_browse"); poll_notify polls your token, and get_outpost_door_state returns the door-state document above.
The count, as of November 1, 2026 — a snapshot, dated on purpose.
Registered intents at Costco, as of November 1, 2026: 0. The registry is open and counting; no agent has registered at this Outpost yet. For this page's task (menu / browse): 0.
These are dated snapshot figures, published as of the date above. Live totals travel with the API: every intent receipt and every notify poll carries the brand's current demand snapshot.
How the count is made: callers are identified by a one-way SHA-256 hash — no raw IP addresses are stored — and registrations are capped at 100 per caller per day and 5,000 per day service-wide, behind an edge rate cap. Treat any count here as a demand signal, not proof of unique agents. Across the whole registry today, the ledger's only entry is Agent Outposts' own labeled internal test; no organic agent demand has been recorded yet.
Five tasks, five door-states — this page is one of them.
Agent Outposts is not affiliated with Costco. This Outpost is a demand registry operated by Agent Outposts; door-states are assessed from public sources, linked, and dated.