refactor: rename agents to runtimes (schema, CLI flags, MCP bindings)

[jesseturner21]

Description

Renames agent terminology to runtime across schema, CLI flags, and MCP bindings to better reflect the resource type (AgentCoreRuntime). This is a breaking change to the agentcore.json schema.

Commit 1: Schema rename agents → runtimes

• JSON schema: agentcore.schema.v1.json property "agents" → "runtimes"
• Zod schemas: agentcore-project.ts, deployed-state.ts
• LLM-compacted types: agentcore.ts, mcp.ts
• Source files: All .agents property accesses on AgentCoreProjectSpec and DeployedResourceState → .runtimes
• Tests: All test fixtures and assertions updated
• Docs: configuration.md JSON examples updated

Commit 2: CLI flags --agent → --runtime

• --agent <name> → --runtime <name> (with -a → -r short alias)
• --agent-runtime-id → --runtime-id
• --agent-arn → --runtime-arn
• --agents → --runtimes (gateway primitive)
• resolveAgent() updated to accept { runtime?: string }
• All action handlers, option types, error messages, and tests updated
• Unchanged: --agent-id, --agent-alias-id (Bedrock Agent IDs), agentcore add agent / agentcore remove agent command names

Commit 3: MCP bindings agentName → runtimeName

• McpRuntimeBindingSchema.agentName → runtimeName
• attach.ts binding logic updated
• JSON schema, LLM-compacted types, and tests updated

NOT changed (intentionally):

• ParsedStarterToolkitConfig.agents — external YAML parser type
• CLI command names (add agent, remove agent)
• --agent-id and --agent-alias-id (Bedrock Agent identifiers)
• Directory paths in codeLocation values

Related Issue

Closes #

Documentation PR

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update
• Other (please describe):

Testing

• I ran npm run test:unit and npm run test:integ
• I ran npm run typecheck
• I ran npm run lint
• If I modified src/assets/, I ran npm run test:update-snapshots and committed the updated snapshots

Results:

• TypeScript: 0 errors
• Unit tests pass (5 pre-existing failures from main: 2 PTY env issues, 3 from PR refactor(schema): remove type fields from resource schemas and rename credential discriminator #709 credential discriminator rename)
• End-to-end tested: create → validate → deploy → status → invoke with --runtime flag

Checklist

• I have read the CONTRIBUTING document
• I have added any necessary tests that prove my fix is effective or my feature works
• I have updated the documentation accordingly
• I have added an appropriate example to the documentation to outline the feature, or no new docs are needed
• My changes generate no new warnings
• Any dependent changes have been merged and published

Companion PR: https://github.com/aws/agentcore-l3-cdk-constructs/pull/124

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[github-actions]

Package Tarball

aws-agentcore-0.3.0-preview.9.0.tgz

How to install

npm install https://github.com/aws/agentcore-cli/releases/download/pr-706-tarball/aws-agentcore-0.3.0-preview.9.0.tgz

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	46%	6553 / 14243
🔵	Statements	45.57%	6963 / 15277
🔵	Functions	44.71%	1176 / 2630
🔵	Branches	46.09%	4331 / 9395

Generated in workflow #1487 for commit 20d0c04 by the Vitest Coverage Report Action