> ## Documentation Index > Fetch the complete documentation index at: https://docs.loci.ng/llms.txt > Use this file to discover all available pages before exploring further. # The frame at a location > Resolves a longitude and latitude to the frame that contains it: the cell's id, its shape, and its bounding box. This is the first call most integrations make. The id it returns is what the other three calls take. A device's own position, a geocoded address, a tapped point on a map: any of them becomes a frame id here. `lng` is accepted as a spelling of `lon`. The answer is cacheable for ten minutes; the grid only changes when it is reloaded. Needs the `frame.read` capability, which every scope preset grants. ## OpenAPI ````yaml /api-reference/openapi.json get /v1/frames/at openapi: 3.1.0 info: title: LOCI API version: 1.0.0 summary: >- The Milsat spatial index over HTTP: find the frame at a location, the frames around it, what is recorded on them, and a worded answer about them. description: >- Four calls, all under `/v1/frames`, all read-only, all with an API key. Nigeria is covered by a grid of **frames**: cells roughly a kilometre across, each with a stable numeric id. Every dataset on LOCI falls within frames, so a frame id is the key to everything known about a place. The API lets your code resolve a location to its frame, list the frames around a point, read what the datasets your organisation owns or licenses record on those frames, and ask a question about them in plain language. Every response is wrapped in an envelope: a success carries `data`, a failure carries `error` with a machine-readable `code` and a human `message`. Branch on the code; the message may be reworded. Send the key as `Authorization: Bearer loci_sk_…`. A key acts for one organisation, is read-only, and expires. servers: - url: https://api.staging.loci.ng description: The LOCI API, which the app at loci.ng also uses. - url: http://localhost:8088 description: A local development stack, which the examples here were captured against. security: - apiKey: [] tags: - name: Frames description: The spatial index and what is recorded on it. paths: /v1/frames/at: get: tags: - Frames summary: The frame at a location description: >- Resolves a longitude and latitude to the frame that contains it: the cell's id, its shape, and its bounding box. This is the first call most integrations make. The id it returns is what the other three calls take. A device's own position, a geocoded address, a tapped point on a map: any of them becomes a frame id here. `lng` is accepted as a spelling of `lon`. The answer is cacheable for ten minutes; the grid only changes when it is reloaded. Needs the `frame.read` capability, which every scope preset grants. operationId: frameAt parameters: - name: lat in: query required: true description: Latitude in degrees, −90 to 90. schema: type: number example: 9.0579 - name: lon in: query required: true description: Longitude in degrees, −180 to 180. `lng` is accepted too. schema: type: number example: 7.4951 responses: '200': description: The frame containing the point. content: application/json: schema: type: object properties: data: $ref: '#/components/schemas/Frame' required: - data example: data: id: '2163551' geometry: type: Polygon coordinates: - - - 7.5003 - 9.05143 - - 7.49131 - 9.05143 - - 7.49129 - 9.05145 - - 7.48751 - 9.05811 - - 7.48753 - 9.06201 - - 7.5003 - 9.06201 - - 7.5003 - 9.05143 bbox: - 7.48751 - 9.05143 - 7.5003 - 9.06201 '400': description: >- `lat` or `lon` is missing, not a number, or out of range. Code `invalid_point`. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: invalid_point message: lon and lat are required, in degrees '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/InsufficientScope' '404': description: The point lies outside the grid. Code `not_found`. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: not_found message: no frame contains that point '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/Internal' components: schemas: Frame: type: object description: A cell of the spatial index. properties: id: type: string description: The frame's stable id, a numeric string. example: '2163551' geometry: $ref: '#/components/schemas/Geometry' bbox: $ref: '#/components/schemas/BBox' required: - id - geometry - bbox Error: type: object properties: error: type: object properties: code: type: string description: Stable and machine-readable. Branch on it. message: type: string description: For people. May be reworded. required: - code - message required: - error Geometry: type: object description: A GeoJSON geometry. properties: type: type: string example: Polygon coordinates: description: Positions as `[lon, lat]`, nested as GeoJSON requires for the type. required: - type - coordinates BBox: type: array description: '`[minLon, minLat, maxLon, maxLat]` in degrees.' items: type: number minItems: 4 maxItems: 4 responses: Unauthorized: description: >- No credential (`unauthorized`), or a key that is unknown, expired or revoked (`invalid_key`). A bad key is not treated as anonymous: the `loci_sk_` prefix proves a key was meant. content: application/json: schema: $ref: '#/components/schemas/Error' examples: none: value: error: code: unauthorized message: sign in, or send an API key invalid: value: error: code: invalid_key message: that API key is not valid, has expired, or was revoked InsufficientScope: description: >- The key does not carry `frame.read`. Every preset grants it, so this only arises on a key minted with an explicit capability list. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: insufficient_scope message: this API key does not carry the frame.read scope RateLimited: description: >- A budget is spent. `Retry-After` says how many seconds until the next request will pass. headers: Retry-After: schema: type: integer description: Seconds to wait. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: rate_limited message: too many requests — retry in 5s Internal: description: >- Something failed on the server. The message is deliberately vague; retry once. content: application/json: schema: $ref: '#/components/schemas/Error' example: error: code: internal message: could not look up the frame securitySchemes: apiKey: type: http scheme: bearer bearerFormat: loci_sk_… description: >- An API key minted in the Developers tab of the LOCI app, sent as `Authorization: Bearer loci_sk_…`. Acts for one organisation, is read-only, and expires. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.