fix(agents): reuse existing azure.yaml agent config on init

[Glenn Harper (glharper)]

Summary

azd ai agent init in a project that already has an azure.yaml re-prompted for agent name, protocols, and deploy mode instead of reading them from the manifest.

Init already detects and reuses an existing agent.manifest.yaml or a bare agent.yaml (the latter added for #7268 — "less to ask and just setup azure.yaml"). But the unified manifest work (d8f3abe) moved the agent definition inline onto the azure.yaml service entry and stopped writing a standalone agent.yaml:

Generate .agentignore. The agent definition is written into the azure.yaml service entry below, not to an on-disk agent.yaml.

The reuse detection was never extended to look there, so a modern project matches neither existing check, falls through to promptInitMode → the from-code path, and re-asks for everything azure.yaml already answers.

Changes

• detectProjectAgentServices — asks the azd host for the project (Project().Get()), validates every azure.ai.agent service path inside the project boundary, and reuses only definitions that resolve through the production inline / deprecated config: / $ref / on-disk agent.yaml loader. Missing or invalid definitions are debug diagnostics, not successful reuse candidates.
• runReuseProjectAgentServices — completes init without re-prompting: host-based detection already proves the project exists, so it ensures the selected azd environment exists and hands that exact environment to the shared next-step resolver
• Wired into RunE after manifest detection but before bare agent.yaml reuse, so a configured disk-backed service is treated as a project no-op rather than being added/replaced from its file

Interactive runs get a confirm (defaulting to yes) matching the sibling detection prompts; declining falls through to today's behavior, so adding a second agent to an existing project still works.

This project already configures "chat" (agent: my-chat-agent). Use it?

Notes

• Project discovery is the host's. Going through Project().Get() rather than reading azure.yaml directly means init sees the same manifest every other azd command does: resolved by walking up from the working directory, and honoring azure.yml as well as azure.yaml. It also reuses core's parsing instead of carrying a second, hand-rolled view of the service schema.
• A service is reusable only when its definition is real. project.LoadAgentDefinition validates inline, deprecated config:, $ref, and on-disk definitions. A bare host: azure.ai.agent entry with no definition no longer makes --no-prompt exit successfully.
• Service source paths stay inside the project. paths.JoinAllowRoot rejects absolute, traversal, and symlink-escaping paths before a service can authorize project reuse.
• Project ownership wins over bare-file detection. Project reuse runs before the shallow agent.yaml scan. This keeps an existing service's uses: and other fields intact when its definition lives on disk.
• A project the host can't load means "no detections", not a hard failure. Project().Get() errors on a malformed manifest (it goes through project.Load). Init treats that as nothing detected and falls through to the normal prompts, rather than failing on a file the user hasn't been asked about yet. The cause is logged, so --debug still surfaces a typo.
• Any agent-defining flag opts out of reuse. --no-prompt makes reuse unconditional, so reusing while the caller passed --deploy-mode, --runtime, --entry-point, --agent-name, --protocol, --model, --model-deployment, --project-id, --image, or --src would silently discard them. Those runs fall through to the normal flow instead. --env and --infra describe the environment and the IaC output rather than the agent, so they stay compatible with reuse.
• Source paths preserve intent. Explicit --src opts out of project no-op reuse but remains valid for bare agent.yaml reuse, which consumes it. A positional project-root or configured service-directory path may reuse; an unconfigured source directory opts out so it is not silently ignored.
• Selected-environment guidance stays selected. State is assembled from --environment without changing azd's active environment, and every emitted azd command is qualified as azd --environment "<name>" ...; non-azd cd / edit / README guidance remains unchanged.
• Adoption (runInitFromAzureYaml) is deliberately not reused here: it refuses when a project manifest already exists, since merging a sample's services into an existing azure.yaml is tracked separately as [ext-agents]: azd ai agent init -m <azure.yaml> should merge into an existing project's azure.yaml #8884. This change is about respecting the manifest already present, not merging a new one in.

Testing

• go test ./... -count=1 (all extension packages)
• go build ./...
• golangci-lint run ./internal/cmd/... — 0 issues
• gofmt -s -l ./internal — clean
• cspell lint on the changed files — 0 issues

New coverage: inline / config: / disk definitions, missing definitions rejected, unsafe absolute / traversal / symlink service paths rejected, deterministic ordering, non-agent hosts ignored, project reuse before disk reuse from a service subdirectory, the project-vs-bare agent-defining flag matrix, positional root / configured service / unconfigured source classification, selected-environment state, and environment-qualified next-step commands.

Fixes #9154

[github-actions]

📋 Prioritization Note

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Thank you for logging this issue; our team is reviewing it. If you need urgent prioritization, tag Rick Winter (@RickWinter) and Kristen Womack (@kristenwomack) to let us know.

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[Copilot]

Pull request overview

Adds reuse of inline agent configuration from an existing project manifest during azd ai agent init.

Changes:

• Detects inline and legacy nested agent definitions.
• Reuses existing configuration without prompting.
• Adds manifest parsing and formatting tests.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
internal/cmd/init.go	Integrates existing-project reuse detection.
internal/cmd/init_reuse_project_agent.go	Implements detection and reuse.
internal/cmd/init_reuse_project_agent_test.go	Tests manifest discovery and parsing.

[Jon Gallant (jongio)]

Two things worth a second look before this merges.

The new azure.yaml reader re-implements parsing the extension already gets from the azd host, and it reads from --src rather than the project root. Details inline on init_reuse_project_agent.go.

The reuse gate only opts out on --agent-name, but --no-prompt makes reuse unconditional, so a scripted run in a repo that already declares an agent silently ignores every other agent-defining flag instead of adding a second agent. Details inline on init.go.

Two smaller ones inline: a validatePostInit call that can't do anything, and a swallowed YAML parse error.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

Suppressed comments (4)

cli/azd/extensions/azure.ai.agents/internal/cmd/init.go:1313

• This fallback misses an azure.yml project when the command is run from a subdirectory. azdext.GetProjectDir only walks upward for azure.yaml (cli/azd/pkg/azdext/project.go:16-35), so checkDir becomes . and the subsequent shallow scan never reaches the parent manifest. Resolve the root using both supported project filenames and add a nested-directory azure.yml test.

				if errors.Is(projectErr, azdext.ErrProjectNotFound) {
					checkDir = "."

cli/azd/extensions/azure.ai.agents/internal/cmd/init.go:1311

• This line is not gofmt-formatted, so the repository's formatting check will fail. Indent it consistently with the surrounding block.

checkDir, projectErr := azdext.GetProjectDir()

cli/azd/extensions/azure.ai.agents/internal/cmd/init.go:1357

• No test executes this new RunE branch or runReuseProjectAgentServices; the added tests only validate YAML scanning and display formatting. Add command-level coverage for interactive accept/decline, no-prompt reuse, explicit-option opt-out, environment creation/reuse, and invocation from a nested project directory so the orchestration—not just its parser—is verified.

							if err := runReuseProjectAgentServices(
								ctx, flags, azdClient, checkDir, displayPath, agentServices,

cli/azd/extensions/azure.ai.agents/internal/cmd/init_reuse_project_agent.go:157

• ensureProject prints Found existing azd project ... Adding agent to it. for an existing project (init.go:1876-1879), but this reuse path intentionally writes no service. Avoid that helper's mutation-oriented status message here, or refactor it so this path can report that the existing configuration is being reused rather than claiming an agent was added.

	if _, err := ensureProject(ctx, flags, azdClient, "."); err != nil {

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Suppressed comments (2)

cli/azd/extensions/azure.ai.agents/internal/cmd/init.go:1074

• A positional directory is also an explicit source selection: applyPositionalArg maps azd ai agent init ./agents/new to flags.src, just like --src. Because srcExplicit only checks Cobra's flag state, this invocation is treated as having no agent-defining input; in --no-prompt mode it silently reuses the existing service instead of initializing the supplied source directory. Preserve reuse only when the positional path resolves to the active project root (the init . case), and treat other positional source paths as opt-outs. [azd-code-reviewer]

		srcExplicit ||

cli/azd/extensions/azure.ai.agents/internal/cmd/init_reuse_project_agent.go:114

• ensureProject's existing-project branch always prints Found existing azd project ... Adding agent to it. (init.go:1882-1885), but this reuse path deliberately writes no service. Every successful reuse therefore emits a false mutation status and may show add-agent-specific infra guidance. Use a read-only project check here, or split the generic project lookup from the add-agent messaging. [azd-code-reviewer]

	if _, err := ensureProject(ctx, flags, azdClient, "."); err != nil {
		return err
	}

[Jon Gallant (jongio)]

One leftover from the rework, not a blocker.

runReuseProjectAgentServices still calls ensureProject, but that call can't do anything on this path anymore. Detection now runs through the host, so reaching the reuse branch already proves Project().Get() succeeded, which makes the scaffold branch inside ensureProject unreachable and its return value discarded.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated no new comments.