# Router Contract Change

> Use when changing a request-visible router contract across configuration, signals, decisions, algorithms, or recipe-scoped plugins in vLLM Semantic Router.

- Skill: `vllm-project/router-contract-change` (Agent Skill)
- Install (CLI): `npx skillmds@latest add vllm-project/router-contract-change`
- Raw SKILL.md: https://api.skillmd.com/api/skills/vllm-project/router-contract-change/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: vllm-project (https://skillmd.com/u/vllm-project)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/vllm-project/router-contract-change

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# Router contract changes

Read the nearest `AGENTS.md` for every touched subtree and
`tools/agent/docs/change-surfaces.md` for the affected contract.

Keep the request-facing entrypoint, isolated recipe, signal/projection inputs,
decision or algorithm, and selected backend/plugin behavior consistent. Update
canonical config, generated or schema-derived artifacts, and user-visible docs
only where that contract changes.

Run `make check` first. Use `make verify DOMAIN=<domain>` for the affected
integration contract, or `make verify PROFILE=<profile>` when behavior crosses
the deployment boundary. A pure refactor does not need new E2E coverage.