Head to head · Decision models · October 2026 research run
pplx-decider vs Vela 2.0
Vela 2.0 scores 66.5 (B) on agent readiness against pplx-decider's 62.9 (B), and leads in 3 of 7 scored categories. pplx-decider leads on schema & documentation. Both do decision models. pplx-decider is cheaper for decision models, $0 against $0 per 1M tokens.
Best decision models for AI agents · All 66 decisions comparisons
Which one, for what
Good for High-volume classification, routing and rubric scoring over text and images where a team wants a low hosted price and the option to run the same weights itself.
Ahead on
- Schema & documentation, 90 against 78
Also in its favour
- Cheaper for decision models, $0 against $0 per 1M tokens
- A hosted endpoint, with nothing to install
Watch for
The Decisions API was released in October 2026, so its incident record is days long, and Perplexity's FAQ says it gives no uptime guarantee
Vela 2.0 B
Good for Self-hosted routing and guardrail checks in one call, where span offsets for personal data or unsupported claims matter.
Ahead on
- Payments & pricing, 60 against 25
- Maintenance & community, 84 against 62
Also in its favour
- No key needed to call it
- Open source
Watch for
No version tags on the four Hub repositories, and the 4B and 9B weights were replaced in place on 3 October 2026
Score by category
| Category | Weight this run | pplx-decider | Vela 2.0 | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 61 | 57 | pplx-decider +4 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 90 | 78 | pplx-decider +12 |
| Agent ergonomics | 13%16.2 | 76 | 79 | Vela 2.0 +3 |
| Security & auth | 14%17.5 | 61 | 60 | pplx-decider +1 |
| Payments & pricing | 10%12.5 | 25 | 60 | Vela 2.0 +35 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 62 | 84 | Vela 2.0 +22 |
| Transparency & trust | 7%8.8 | 52 | 48 | pplx-decider +4 |
| Negative events | ≤15 | 0 | 0 | |
| Total | 62.9 · B | 66.5 · B |
Facts side by side
| Fact | pplx-decider | Vela 2.0 |
|---|---|---|
| Kind | Model API | Model API |
| Vendor | Perplexity | vLLM Semantic Router project and KR Labs |
| Hosted endpoint | https://api.perplexity.ai/v1/decisions | no (local only) |
| Transports | HTTP | HTTP |
| Auth | API key | None |
| Pricing | Pay per use | Free |
| Price for decision models | free | free |
| x402 | no | no |
| Licence | Apache-2.0 for the published weights. The hosted Decisions API is a proprietary service | Apache-2.0 (weights, code and documentation). The 0.3B's tokeniser keeps the Gemma Terms of Use, and training data keeps its own licences |
| Read-only variant documented | no | no |
| llms.txt | yes | no |
| Last release | 2026-10-05 | 2026-10-06 |
| Terms last updated | couldn't be read | no document linked |
| Privacy policy last updated | couldn't be read | no document linked |
| Customer content may train models | couldn't be read | |
| Terms restrict automated access | couldn't be read | |
| Terms restrict benchmarking | couldn't be read | |
| Terms or service can change without notice | couldn't be read | |
| Arbitration or class-action waiver | couldn't be read | |
| Popularity | none | 6.1k stars |
Verdicts
pplx-decider
The hosted Decisions API has an OpenAPI description, typed questions, documented limits and a published price of $0.02 per million input tokens, and the v1.1 weights are public under Apache-2.0. The API is days old, the official Python SDK has no method for it, and the governing terms and privacy notice could not be read on 9 October 2026.
Vela 2.0
One self-hosted call answers routing, prompt-attack, personal-data and unsupported-claim questions with probabilities and character offsets, under Apache-2.0 with SHA-256 manifests. The models are days old and carry no Hub version tags, and the three larger sizes keep 74 to 89 per cent of their Decision 2.0 bases on the Jev Decision Index by the authors' figures.
Before you call either
pplx-decider
- Send
Authorization: Bearer. A key inx-api-keyreturns 401 on this endpoint. - Set
modelon every request. A missing or unknown model returns 400, and the guide shows a-latestname rejected. - Resize images to 2,048 tiles of 32 by 32 pixels or fewer before sending. Larger images end in a 504 after about a minute.
- Check the HTTP status before parsing an error. 404 and 405 have empty bodies, 504 can be HTML, and
error.codechanges type. - For the weights, use the repository's
autojevcode. The card says default causal inference does not reproduce the evaluated setup.
Vela 2.0
- Pin a commit hash with
revision=when loading from the Hub. The repositories have no tags andmainhas changed since launch - Send the served name in
model, for examplevllm-sr/Vela-2.0-4B. The bundled server answers 422 to any other name - Name span questions
pii,haluortoxic, or set"head": "router", to get the trained router head. Other labels go to the broad head - Keep input under 16,384 tokens a sequence (8,192 on the 0.3B). The bundled server answers 413 when the questions alone don't fit
- Set
VELA2_API_KEYbefore binding the bundled server beyond 127.0.0.1, and keep the model runtime on a trusted network
Questions
Which is better for AI agents, pplx-decider or Vela 2.0?
Vela 2.0 scores 66.5 (B) on agent readiness against pplx-decider's 62.9 (B), and leads in 3 of 7 scored categories. pplx-decider leads on schema & documentation.
Which is cheaper for decision models, pplx-decider or Vela 2.0?
pplx-decider, at free against free for Vela 2.0. These are the vendors' published prices for the job.
Do pplx-decider and Vela 2.0 need an API key?
pplx-decider needs an API key. Vela 2.0 needs no key.
Can an agent call pplx-decider and Vela 2.0 without installing anything?
pplx-decider has a hosted endpoint at https://api.perplexity.ai/v1/decisions. No hosted endpoint is listed for Vela 2.0.
Are pplx-decider and Vela 2.0 open source?
No open-source release is listed for pplx-decider. Vela 2.0 is open source (Apache-2.0 (weights, code and documentation). The 0.3B's tokeniser keeps the Gemma Terms of Use, and training data keeps its own licences).
Other comparisons with pplx-decider or Vela 2.0
- Celeris-1 Decision vs pplx-decider
- Celeris-1 Decision vs Vela 2.0
- Clef vs pplx-decider
- Clef vs Vela 2.0
- Laya vs pplx-decider
- Laya vs Vela 2.0
- Decider vs pplx-decider
- Decider vs Vela 2.0
- GLiClass vs pplx-decider
- GLiClass vs Vela 2.0
- Kev vs pplx-decider
- Kev vs Vela 2.0
- Liquid d1 vs pplx-decider
- Liquid d1 vs Vela 2.0
- OpenAI Decisions API vs pplx-decider
- OpenAI Decisions API vs Vela 2.0
- pplx-decider vs Strands Decider 2B
- pplx-decider vs Jev
- Strands Decider 2B vs Vela 2.0
- Jev vs Vela 2.0
Machine-readable
- This page as Markdown
/compare/pplx-decider-vs-vela.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/pplx-decider.json·/api/v1/tools/vela.json - From a terminal
anchor compare pplx-decider vela(the CLI) - Over MCP
compare_tools {"a": "pplx-decider", "b": "vela"}at/mcp, no key