Reference

Limits and scope

What the hub does not do, how big things can be, and where the edges are.

Knowing what a thing refuses to do is half of trusting it. This page is the other half of the hub.

Scope

In	Out
Finding a model, listing its files, getting a URL and the hash	Serving weights; every byte comes from a source
Trending open models, indexed daily	All of Hugging Face; a model not in the index answers `404` and is queued
One revision per model: the one indexed	Arbitrary revisions or branches
Public models	Gated and private models; they are refused, not proxied
Reading, anonymously	Inference; `/v1/` is reserved and deliberately empty

Inference stays out because the hub has no GPUs, and the engines it feeds already speak the OpenAI API.

Sizes

Limit	Value
Models in the index	about 500 on the site and in search, refreshed daily; 575 in today's catalog object
`limit` on `/api/models`	1 to 500, default 50
Publish, one request at the edge	8 MiB
Publish, one message at the server	32 MiB; larger payloads go as 16 MiB chunks joined by a source record
Catalog object	about 380 KB, uncompressed; read it once a day, not once a query

The server states its own ceiling; ask it rather than this page when they disagree:

curl -s https://gethologram.ai/api/v1/capabilities

{
  "protocol_version": 1,
  "server_version": "1.0.0",
  "server_id": "ed25519:b0a1e6c0cf0d4aa5a31bb0e1a5d8fdbd3e1d40b3a5c8f2ee71f6c9a0d4b27e15",
  "role": "node",
  "maximum_message_bytes": 33554432,
  …
}

Whether sign-in is available on this deployment:

curl -s https://gethologram.ai/api/account/health

{ "ok": true, "configured": true }

Rates

Reads are anonymous and not metered by the hub. The sources the hub redirects to have their own limits: Hugging Face rate-limits anonymous downloads per IP, and the IPFS gateway is slower on a cold read. Writes to /api/account/* answer 429 when one account writes too often.

Caching

Path	Cache
`/api/v1/objects/<address>`	forever; an address never changes meaning
`/api/models…`, `/tree/…`, `/refs`	60 s
`/resolve/…` redirects	not cached; the source may change between two requests
`/openapi.json`, `/agent.md`, `/robots.txt`	5 min

Compatibility

Works	Does not
Anything that reads `HF_ENDPOINT` or `MODEL_ENDPOINT`	LM Studio, Jan, `docker model pull hf.co/…`: the host is hardcoded
Any OCI client that follows a blob redirect and verifies digests	Formats with tar layers, such as KitOps ModelKit
Ollama 0.34 and later
MCP clients on Streamable HTTP	MCP over stdio or SSE
A browser on any origin: every read route sends `Access-Control-Allow-Origin: *`

Reporting

A model that should be in the index: POST /api/account/request from a signed-in account, or open an issue on the repository. A file whose bytes never match the index from any source is an index bug; report it the same way, with the model id, the path and the SHA-256 you observed.