feat(providers): add Concentrate provider preset

[kevincodex1]

Summary

Adds Concentrate (https://concentrate.ai) as a built-in provider preset. Concentrate is an OpenAI-compatible gateway to models from many labs. It is already in the README Partners section (#1126). This PR adds the provider itself, so zero providers setup concentrate --set-active works the same way the GMI Cloud preset does (#1127).

What changed

• internal/providercatalog/catalog.go: new OpenAI-compatible descriptor.

  • id concentrate, name Concentrate
  • base URL https://api.concentrate.ai/v1
  • key env CONCENTRATE_API_KEY
  • default model deepseek-v4-flash-0731
  • alias concentrate ai, which also matches Concentrate AI, concentrate.ai and concentrate-ai after id normalization.

  models.dev has no Concentrate provider, so the id and key name follow OpenClaude's Concentrate integration.

• Why the default is a dated id. OpenClaude defaults to deepseek-v4-flash, but Concentrate's /v1/models lists that name only as an alias of deepseek-v4-flash-0731.

  • Zero's discovery reads ids, not aliases.
  • Onboarding keeps the default selected only when it matches a live id.
  • With the alias as default, the interactive setup jumped to the first model in the list after a key was entered. That model is claude-fable-5, at $10 / $50 per million tokens.
  • The dated id avoids that and is the same model.

• internal/providermodelcatalog/catalog.go: four curated models, with the context window, tool-calling and thinking flags taken from Concentrate's public GET /v1/models:

  Model	Context (max_input_tokens)	Max output (max_tokens)
  deepseek-v4-flash-0731 (default, alias deepseek-v4-flash)	1,048,576	393,216
  deepseek-v4-pro	1,048,576	393,216
  kimi-k3	1,048,576	262,144
  glm-5.3	1,048,576	262,144

  The curated model type has no max-output field, so the output limits are recorded in a code comment only.

• Tests:

  • descriptor test and alias cases in catalog_test.go;
  • catalog-order lists;
  • the onboarding hint test in internal/cli;
  • a model-scope case plus a test that pins the curated IDs, context windows and source;
  • regression test TestDiscoverCatalogConcentrateKeepsDefaultModelInLiveList. It serves a Concentrate-shaped /v1/models (dated ids, rolling names in aliases) and requires the preset's default to be among the discovered models.

• README.md and README_ZH.md: the CONCENTRATE_API_KEY line and the setup command. The existing partner entry is unchanged.

How it was tested

• make fmt-check, gofmt -l and git diff --check: clean.

• go vet on the touched packages: clean.

• go build ./...: passes.

• Package tests pass:

  • go test ./internal/providercatalog/... ./internal/providermodelcatalog/... ./internal/providermodeldiscovery/...;
  • the internal/cli onboarding hint test, including the concentrate subtest.

• The regression test fails when the default is set back to deepseek-v4-flash: "default model "deepseek-v4-flash" missing from discovered models "claude-fable-5,deepseek-v4-flash-0731,…"". It passes with the fix.

• Full suite: go test ./... passes for 89 packages, except for 25 sandbox tests in agent, cli, sandbox, tools and tui.

  • Those 25 tests fail the same way on a clean origin/main checkout in the same directory, which is under /private/tmp.
  • The tests create their "outside the workspace" folder inside the package directory, and the sandbox always allows writes under /private/tmp.
  • They are unrelated to this change and should pass in a checkout outside /tmp.

• go run ./cmd/zero-release build and smoke: pass. make vulncheck: no vulnerabilities found.

• An independent review of the diff checked:

  • that every place the GMI preset is registered also has Concentrate;
  • that all curated ids and limits match the live /v1/models;
  • that the aliases resolve;
  • that the README_ZH line means the same as the English one.

  It found the default-model issue above, which is fixed here.

• Manual CLI checks with a throwaway HOME:

  • zero providers catalog shows the new entry.
  • zero providers setup concentrate --set-active prints the providers add command.
  • zero providers add saves the profile.
  • With no key, zero providers check concentrate --connectivity fails with "Provider concentrate requires API credentials."
  • zero providers models concentrate lists all 196 models without a key, because /v1/models is public.

• Live chat check with a real key: not run yet. The key was not available while this branch was prepared. To finish it:

  export CONCENTRATE_API_KEY=...
  zero providers add concentrate --api-key-env CONCENTRATE_API_KEY --set-active
  zero providers check concentrate --connectivity
  zero exec "Reply with exactly one word: pong"

Notes and follow-ups (not changed here)

• Context sizes after a key is entered. Zero's live discovery does not read Concentrate's top-level max_input_tokens. Once a key exists, the live list replaces the curated one and shows no context sizes, so compaction uses the 200K fallback. A follow-up should read max_input_tokens in modelsResponseItem, as OpenClaude does.
• The connectivity check passes with any key. Concentrate's /v1/models answers 200 with no key or a wrong key, so providers check --connectivity passes with a mistyped key; the first chat then fails. OpenRouter behaves the same way.
• Keyless chat calls return an HTML page. Concentrate's Cloudflare answers a keyless chat call with a 403 HTML block page, and zero exec prints the whole page, including the caller's IP. This is existing behaviour for any provider that returns HTML on 401/403.
• Found on main while testing, separate from this PR: the models.dev catalog fetch fails for every provider. https://models.dev/api.json is now 5.66 MB, and fetchJSON stops reading at 4 MiB (internal/providermodelcatalog/remote.go), so decoding fails with "unexpected end of JSON input".

Summary by CodeRabbit

• New Features
  • Added Concentrate as an available AI provider, with four listed models supporting tool calling and reasoning.
  • Added live model discovery for Concentrate, including models available beyond the curated list.
  • Added Concentrate setup guidance, including its API key and a command to configure it as the active provider.
• Documentation
  • Updated the English and Chinese first-run instructions with Concentrate configuration details.

[github-actions]

Zero automated PR review

Verdict: No blockers found

Blockers

• None found.

Validation

• [pass] Diff hygiene: git diff --check
• [pass] Tests: go test ./...
• [pass] Build: go run ./cmd/zero-release build
• [pass] Smoke build: go run ./cmd/zero-release smoke

Scope

Head: 628345e560a0
Changed files (8): README.md, README_ZH.md, internal/cli/provider_catalog_onboarding_test.go, internal/providercatalog/catalog.go, internal/providercatalog/catalog_test.go, internal/providermodelcatalog/catalog.go, internal/providermodelcatalog/catalog_test.go, internal/providermodeldiscovery/discover_fallback_test.go

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📒 Files selected for processing: 1

• internal/providermodeldiscovery/discover_fallback_test.go

🚧 Files skipped from review as they are similar to previous changes: 1

• internal/providermodeldiscovery/discover_fallback_test.go

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Walkthrough

The change adds Concentrate as an OpenAI-compatible provider and defines four catalog models. Catalog and discovery tests cover the provider configuration, model attributes, and live model results. English and Chinese First Run instructions now show the API key variable and setup command.

Changes

Concentrate provider

Layer / File(s)	Summary
Provider registration and setup internal/providercatalog/catalog.go, internal/providercatalog/catalog_test.go, internal/cli/provider_catalog_onboarding_test.go, README.md, README_ZH.md	The provider catalog defines Concentrate with its endpoint, default model, API key variable, and aliases. Tests cover its descriptor, aliases, transport, and runtime onboarding. Both README files show the API key variable and setup command.
Concentrate model catalog and discovery internal/providermodelcatalog/catalog.go, internal/providermodelcatalog/catalog_test.go, internal/providermodeldiscovery/discover_fallback_test.go	The model catalog adds four models with context and capability fields. Tests check the catalog entries and verify that live discovery includes a live-only model and the configured default model.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~12 minutes

Change: Feature

Merge Risk: ⚪ Minimal · up to 62834

No actionable issue remains in the supplied review evidence; the change is mergeable after normal checks.

Pre-merge checks: 4 · 1

Failed checks: 1 warning

Check name	Status	Explanation	Resolution
Docstring Coverage		Docstring coverage is 16.67% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 12 functions across 6 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

Passed checks: 4 passed

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly and concisely identifies the main change: adding a built-in Concentrate provider preset.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

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Inline comments:
Review comments at @internal/providermodeldiscovery/discover_fallback_test.go:
- Around line 76-82: Update the discovery test around modelIDs to assert a model
present only in the mock live response, and verify the mock received the
/v1/models request. Do not rely on provider.DefaultModel, which may also appear
in the fallback catalog.

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📥 Commits

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📒 Files selected for processing: 8

• README.md
• README_ZH.md
• internal/cli/provider_catalog_onboarding_test.go
• internal/providercatalog/catalog.go
• internal/providercatalog/catalog_test.go
• internal/providermodelcatalog/catalog.go
• internal/providermodelcatalog/catalog_test.go
• internal/providermodeldiscovery/discover_fallback_test.go

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