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Bluesky / AT Protocol PDS — 5 MiB blob default, GC'd unless referenced

github.com/bluesky-social/atproto/blob/main/packages/pds/srcAtproto pdsstorage/bluesky-at-protocol-pds-5-mib-blob-default-gc-d-unless-rJSON compare report an error provider JSON

Free allowance: BlobUploadLimit defaults to 5 * 1024 * 1024 = 5 MiB per blob, overridable per-PDS via the BLOB_UPLOAD_LIMIT env var.
Verdict: fails: quotathe free allowance is too small to matter
Cost: free tier
Identity: email?placeholder, not evidence; card unknown, phone unknown
Binding limit: per-object-cap5 MiB per blob
Evidence: reported2 sources; a third party said so
Freshness: stale on 2026-11-05checked 2026-10-21 (inherited); stale on 2026-11-05

Free tier	blobUploadLimit defaults to 5 * 1024 * 1024 = 5 MiB per blob, overridable per-PDS via the BLOB_UPLOAD_LIMIT env var. Per-account: bsky.app's hosted PDS is generous in practice but the protocol layer only guarantees blobs that are REFERENCED by a record. unit mixed; metered on unstated
Price	none stated
Limits	per-object-cap (binding) 5 MiB per blob source per-object-cap 5 MiB default (config.ts: `blobUploadLimit: env.blobUploadLimit ?? 5 * 1024 * 1024`); blobs unreferenced within a time window (minutes) are deleted; account-level repo size limits are enforced by the AppView/PDS separately.
Identity	email (placeholder) not published
Egress	Free on bsky.app's PDS and on any self-hosted PDS (it serves blobs directly from /xrpc/com.atproto.sync.getBlob). No egress meter.
Per-object cap	5 MiB per blob (5242880 bytes)
Retention	not stated
Interface	cli http-xrpc
Tooling	XRPC: POST /xrpc/com.atproto.repo.uploadBlob (binary body + Content-Type) -> returns a `blob` ref; must then be referenced by a record (e.g. app.bsky.feed.post embed) or it is garbage-collected. Client libs: @atproto/api, atproto Python SDK, `goat` CLI.
Composes with	Self-hosting a PDS removes the 5 MiB default (it is a config value), so a self-hosted PDS is bounded by YOUR disk, not Bluesky's — that makes it a hosting product, not free storage. On bsky.app's PDS the 5 MiB cap plus the reference requirement makes it useless for bulk. The usable margin is only the 'unreferenced blobs are deleted within minutes' semantics working in reverse: referenced blobs are retained indefinitely.
Reliability	Blob GC is literal and fast — an upload without a referencing record vanishes. That is the single most important fact about this candidate.
Parsed numbers	has-free-tier 1 per-object-cap 5 MiB

Evidence 2

date	source	what it proved
2026-10-21	raw.githubusercontent.com/bluesky-social/atproto/main/packag	`blobUploadLimit: env.blobUploadLimit ?? 5 * 1024 * 1024, // 5mb`
2026-10-21	raw.githubusercontent.com/bluesky-social/atproto/main/lexico	'The blob will be deleted if it is not referenced within a time window (eg, minutes). Blob restrictions (mimetype, size, etc) are enforced when the reference is created. Requires auth, implemented by PDS.'

More fields 2

unit note	free_tier.unit is 'mixed' because the headline is denominated in MiB or KiB, which the schema enum does not carry; the verbatim free_tier.stated keeps the true unit.
dead end	`{"failure_class": "quota","why": "blobUploadLimit defaults to 5 * 1024 * 1024 = 5 MiB per blob, overridable per-PDS via the BLOB_UPLOAD_LIMIT env var. Per-account: bsky.app's hosted PDS is generous in practice but the protocol layer only guarantees blobs that are REFERENCED by a record.","retry_when": null,"first_recorded": "2026-10-21"}`

Unknown values 3

per object cap notes: the field may be stated in a source that was not read
retention notes: the field may be stated in a source that was not read
retention stated: the field may be stated in a source that was not read