ADR 0155: Add Zhipu / Z.AI Named Endpoint Presets

• Status: Accepted
• Date: 2026-09-05
• Deciders: PI-Desktop core
• Updates ADR 0012, ADR 0020, and ADR 0116

Context

Zhipu AI (智谱) exposes two product modes and two regions:

• Standard API vs GLM Coding Plan
• China (open.bigmodel.cn) vs international (api.z.ai)

pi-ai already ships Completions transports for the two Coding Plan URLs (zai, zai-coding-cn) and detects thinkingFormat: "zai" from those hosts. models.dev already publishes all four endpoints. PI-Desktop's add-provider dialog was a generic OpenAI-compatible form, so users had to know which URL to paste, and a saved row used vendorKey: "custom".

Issue #35 asked for first-class configuration of API vs Coding Plan and China vs international, without a new vendor SDK.

Decision

Expose four named endpoint presets in the add-provider Service select. They stay on the existing OpenAI-compatible path:

vendorKey              baseUrl
zhipuai                https://open.bigmodel.cn/api/paas/v4
zhipuai-coding-plan    https://open.bigmodel.cn/api/coding/paas/v4
zai                    https://api.z.ai/api/paas/v4
zai-coding-plan        https://api.z.ai/api/coding/paas/v4

Selecting a preset fills the name, locks the Base URL, keeps apiStyle: "chat_completions", and persists the models.dev vendorKey. The display name stays editable. Coding Plan shows a one-line API-key hint. This is a compact select, not a restored vendor-card grid.

pi-ai's zai transport is the international Coding Plan, while models.dev zai is the standard API. PI-Desktop stores the models.dev key plus the exact URL so catalog matching cannot confuse them. zai-coding-cn remains an alias of zhipuai-coding-plan.

When the configured URL or vendorKey matches a preset, the sidecar Completions model record receives thinkingFormat: "zai" and zaiToolStream: true. No new wire adapter, secret table, or host protocol is introduced.

Consequences

• China and international Zhipu users can pick API vs Coding Plan without copying URLs from external docs.
• Catalog enrichment follows the selected endpoint, not a generic custom row.
• Generic OpenAI-compatible configuration remains the Custom endpoint option.
• OpenCode Go stays an API-style preset; Zhipu does not add four more apiStyle values.