Tag Data Loader (E621)

This is the retrieval half of Lazy Pony Prompter's save system for e621 tag pulls. You name a previously saved collection, this node hands it back, and you plug it into the E621 source node instead of re-running a live query. It's a genuinely small node - one dropdown, one output - and that's by design: the work happens elsewhere, this just gets you back to a known-good tag pool.

Why you'd reach for it

e621's tagging is dense - the site requires at least ten general tags per upload across categories like character, species, and general description - which means a good query against it can surface a genuinely well-tagged, high-signal pool of prompts. That's worth keeping. Re-querying every session risks pulling a different, worse set of images the next time around, plus it's an unnecessary network round-trip if you already found what you needed. Save the pull once with Tag Data Saver, and the Loader gets you back to that exact pool on demand, offline, no API call required.

This matters more for e621 specifically than it might for a general-purpose source: if you're doing EasyFluff or SeaArt Furry work and found a query that reliably returns clean species/character tag combos, that's a query worth locking in rather than re-rolling the dice on every session.

The inputs and outputs that matter

One field: collection_name, an enum dropdown of your saved e621 collections. Empty until you've saved at least one - that's expected behavior, not a broken install.

The output, tag data, is typed LPP_TAG_DATA_E621 - booru-specific, matching exactly what the E621 source node's optional tag_data input expects. Wire this in, turn send_request off on the source node, and it re-rolls prompts from your saved collection instead of querying e621 fresh. You can still change the source node's format (EasyFluff, SeaArt Furry v1.0, Pony Diffusion V5(.5)/V6, and so on) or prompt_template against the same loaded data - reformatting doesn't require a re-fetch.

How to install it

It's part of the Lazy Pony Prompter pack - no separate install for individual nodes. ComfyUI Manager: search "Lazy Pony Prompter," install, restart. Manual:

cd ComfyUI/custom_nodes
git clone https://github.com/Siberpone/lazy-pony-prompter

Restart ComfyUI. No model downloads, no extra pip dependencies to track down - it's just Python glue around a couple of booru APIs. All LPP nodes sit under the LPP group; this one's under LPP/loaders.

Common issues & troubleshooting

Dropdown has nothing in it. By far the most common thing that trips people up on this node - and it's not a bug. You need to save something first. Run E621 with send_request on, feed its LPP Tag Data output into Tag Data Saver, give it a name, and this dropdown will pick it up.

Not the collection you expected. If a name got reused, whatever saved second either overwrote the first (if overwrite was set) or was rejected outright. Check what actually got saved under that name rather than assuming this node loaded the wrong thing.

Won't connect where you expect. The output type here (LPP_TAG_DATA_E621) only matches the E621 source node's tag_data input - it won't plug into Danbooru or Derpibooru source nodes, and it's a different type from what Tag Data Saver takes as input (that one wants the generic LPP_TAG_DATA the source node's main output produces). A refused connection almost always means a type mismatch, not a bug.

Odd behavior in general. The author is upfront that the ComfyUI side of this pack is "somewhat experimental and may have some bugs," with interface compromises made to fit ComfyUI's node model. Minor rough edges are a known, stated tradeoff - not something you're doing wrong.