Lone Trail Gear API and Muse Connector

Lone Trail publishes a small, read-only API so AI assistants (Meta's Muse first, others welcome) can answer the questions hunters actually ask us: will my binoculars fit the harness, will my rangefinder fit the pouch, LT1 or LT2, what attaches to it, what does a full chest rig weigh and cost, what is in stock. The same data runs the Will my binoculars fit? page on this site.

What it knows

  • Binocular fit. Published dimensions for hundreds of binocular models, checked against the harness compartment we measured ourselves (6 in wide, 7.1 in tall, 3 in deep; identical on the LT1 and LT2).
  • Rangefinder fit. Published dimensions for hunting rangefinders, checked against both Lone Trail pouches: the magnetic-lid pouch that ships on every harness (3.3 in wide by 4 in tall) and the standalone Universal Rangefinder Pouch (3.25 in wide, 5 in tall, 2.5 in deep). The rule is strict: a rangefinder may not exceed the pouch on any judged dimension, and the answer says which pouch takes it: the included one, the Universal, both or neither.
  • Products. Verified weights, dimensions with their meaning (exterior vs compartment), materials, what is in the box and what is not, care, and reviewed accessory compatibility with mounting positions.
  • Live commerce. Price, in-stock status and images straight from lonetrail.co at request time. Never exact inventory counts.

How fit results are labeled

Status Meaning
calculated_fit Every published dimension clears our measured compartment or pouch with margin. Calculated, not physically tested.
borderline One dimension is within the give of the fabric case or lid. Expect a snug fit.
does_not_fit A dimension is over the limit by more than the case can give.
unknown The model is not in our data, a dimension is missing, or the pouch has not been measured. The API asks for measurements instead of guessing.

Binocular margins come from real fit reports: width is where harness complaints happen, so a fit needs 0.3 in of side room; length may run 0.2 in snug. Rangefinder pouches have no snug band: the rangefinder either stays within the pouch's published size or it does not. Every answer carries the numbers it used, the source of each dimension, and warnings for estimated or stale data.

Tools and endpoints

MCP endpoint (streamable HTTP, JSON only): POST https://lt-gear-api.awillen.workers.dev/mcp
OpenAPI document: https://lt-gear-api.awillen.workers.dev/openapi.json
No authentication. Rate limit 120 requests per minute per client.

Tool What it does
search_products
GET /v1/products 		Search Lone Trail products
Search Lone Trail's published hunting gear (bino harnesses, harness accessories, game bags, the SB1 backpack) with live price and in-stock status from lonetrail.co. Use for 'what does Lone Trail sell', 'in-stock gear under $X', or to find a product handle for get_product. Returns only published products; never exact inventory counts.
get_product
GET /v1/products/{handle} 		Get one Lone Trail product
Structured facts for one Lone Trail product by handle: what it is, verified weight, dimensions with their meaning (exterior vs compartment vs usable), materials, what is in the box and what is not, where it mounts, care, plus live price, stock and images. Handles: lt1-bino-harness, lt2-bino-harness, universal-rangefinder-pouch, bottom-pouch, bear-spray-holster, binocular-tethers, rangefinder-tether-set, insulated-hand-muff, game-bags, sb1-25l-hunting-backpack.
check_bino_fit
POST /v1/fit/binoculars 		Will these binoculars fit a Lone Trail harness?
Check whether a binocular fits the Lone Trail LT1 / LT2 bino harness (one shared 6 x 7.1 x 3 in compartment). Pass brand + model (database of 726 models with published dimensions) or the user's measurements. Result is a calculated fit from published dimensions, labeled calculated_fit / borderline / does_not_fit / unknown, never a physical test. When the model is unknown or ambiguous the tool says so and asks for dimensions instead of guessing.
check_rangefinder_fit
POST /v1/fit/rangefinders 		Will this rangefinder fit a Lone Trail pouch?
Check a handheld rangefinder against both Lone Trail pouches: the magnetic-lid pouch that ships on every LT1 / LT2 (3.3 W x 4 H in) and the standalone Universal Rangefinder Pouch (3.25 W x 5 H x 2.5 D in). Strict rule: a rangefinder may not exceed the pouch on any judged dimension. Pass brand + model (database of 147 hunting rangefinders) or measurements. Returns a verdict per pouch and a one-line summary (both / harness pouch only / universal only / neither / unknown). Calculated from published dimensions, not a physical test.
compare_harnesses
POST /v1/harnesses/compare 		Compare the LT1 and LT2
Side-by-side LT1 vs LT2: fabric, weight, what ships in the box, storage, magnets, live price and stock, and (optionally) fit for a stated binocular. Both share one binocular compartment, so the comparison is about fabric, storage and price, not fit. Use for 'LT1 or LT2?', 'what's the difference'.
get_compatible_accessories
GET /v1/products/{handle}/accessories 		What attaches to this Lone Trail product?
Reviewed accessory relationships for a Lone Trail base product (LT1, LT2, SB1 or an accessory): which Lone Trail products attach, where they mount (side_left, side_right, bottom, tether_anchor, belt), constraints such as 'the bottom webbing takes one hanging accessory at a time', plus live price and stock. Only explicit reviewed relationships are returned; anything not reviewed is reported as unknown rather than inferred from matching MOLLE.
build_chest_rig
POST /v1/configure/chest-rig 		Build a Lone Trail chest rig
Assemble a compatible Lone Trail chest rig for the user's binoculars and needs: picks the harness (fit is a hard constraint), decides whether the included rangefinder pouch takes their rangefinder or the Universal Rangefinder Pouch is needed, adds only reviewed-compatible accessories with a placement each (bear spray, extra storage, cold-weather hand muff, tethers), and returns known combined weight, live subtotal and stock. Never includes an accessory whose compatibility is unreviewed; never claims a total weight if a component weight is missing.
calculate_gear_weight
POST /v1/weight 		Weigh a Lone Trail loadout
Total known weight (ounces and pounds) for a list of Lone Trail products with quantities, using verified product weights only. Returns per-line weights, whether the total is complete, and which items had no weight on file.

Example

POST https://lt-gear-api.awillen.workers.dev/v1/fit/binoculars
{"brand": "Vortex", "model": "Viper HD 12x50"}

→ status "calculated_fit": 6.5 in long clears the 7.1 in compartment height with 0.2 in to spare;
  5.2 in wide clears the 6 in width with 0.3 in to spare; thickness is an estimate (warning included).

Data and privacy

  • Product facts are maintained by Lone Trail and versioned (current data version 2026-09-19.2).
  • Binocular and rangefinder dimensions come from manufacturer spec pages and manuals, with the source URL on every record. We never invent a dimension; estimated values are flagged.
  • The API is read only. It has no access to customer accounts, orders, addresses, payments, costs or inventory counts, and it cannot place orders or create carts.
  • We log which tool was called, whether it succeeded, how long it took, and the normalized brand/model asked about, so we can research the optics people ask for that we cannot answer yet. No prompts, no emails, no personal data; the requesting address is stored only as a salted daily hash for abuse filtering.
  • Terms: terms of service. Privacy: privacy policy.

Support

Questions, wrong results, or a binocular or rangefinder we should add: email info@lonetrail.co or use the contact page. Shoppers can also report a fit result directly from the fit checker.