Allow MCP agent to override CLI and Config log levels (Agent > CLI > Config)

[anushakolan]

Why make this change?

Closes #3533— Log-level precedence should be Agent > CLI > Config; MCP logging/setLevel is silently ignored when CLI/Config set a level.

The runtime today implements CLI > Config > Agent: once --LogLevel is passed or runtime.telemetry.log-level is set, the agent's request silently no-ops. There is no way for an agent to dial verbosity up or down at runtime, which defeats the purpose of MCP logging/setLevel.

The team locked the corrected precedence on 5/1 : Agent > CLI > Config > defaults. The agent must always be able to override; CLI still beats Config when the agent doesn't speak up; defaults (Production = Error, Development = Debug, --mcp-stdio = None) are unchanged.

What is this change?

DynamicLogLevelProvider is the single chokepoint for all log-level updates. The fix:

• UpdateFromMcp no longer rejects when CLI or Config has set a level. It updates the level, flips a new IsAgentOverriding flag, and emits an Information audit log ("Log level updated to {Level} via MCP logging/setLevel (agent override).").
• UpdateFromRuntimeConfig is guarded so a config hot-reload won't overwrite an Agent- or CLI-set level.
• ILogLevelController gains IsAgentOverriding and updated XML docs.
• Startup.cs wires a logger on the provider once ILoggerFactory exists, so the audit log reaches the standard pipeline.
• McpStdioServer.HandleSetLevel enables the MCP notification writer before calling UpdateFromMcp so the audit log surfaces to the agent.

CLI > Config, default levels, and the --mcp-stdio default of None are unchanged.

How was this tested?

• Integration Tests
• Unit Tests
• Manual end-to-end test against live SQL Server with the MCP Inspector

Unit tests

Added 1 new test and updated existing ones in DynamicLogLevelProviderTests to lock Agent > CLI > Config under both single-call and concurrent paths. All 9 tests pass.

Manual end-to-end test

Started the engine with --mcp-stdio --LogLevel Error and drove it from the MCP Inspector against a live SQL Server.

#	What	How	Result
1	Agent sets level to debug	Send logging/setLevel { level: "debug" }	Success response ✅
2	Audit log surfaces	Watch MCP notifications	Info notification with override message received ✅
3	Debug logs flow despite --LogLevel Error	Trigger activity (e.g. tools/list)	Debug notifications received ✅

Also spot-checked HTTP mode: Config-only, CLI-over-Config, and Config-alone all behave as before.

Sample Request(s)

MCP logging/setLevel from the agent

Request:

{
  "jsonrpc": "2.0",
  "id": 2,
  "method": "logging/setLevel",
  "params": { "level": "debug" }
}

Response:

{ "jsonrpc": "2.0", "id": 2, "result": {} }

Followed by the new visibility notification:

{
  "jsonrpc": "2.0",
  "method": "notifications/message",
  "params": {
    "level": "info",
    "logger": "Azure.DataApiBuilder.Service.Telemetry.DynamicLogLevelProvider",
    "data": "Log level updated to Debug via MCP logging/setLevel (agent override)."
  }
}

CLI usage (precedence still works as expected)

# Agent can override even when CLI pins the level:
dab start --mcp-stdio --LogLevel Error
# → agent sends logging/setLevel debug → debug logs flow

# CLI still beats Config when no agent is involved:
dab start --LogLevel Warning --config dab-config.json   # config has log-level: Information
# → only Warning and above appear

# Config alone, no CLI, no agent — unchanged:
dab start --config dab-config.json                      # config has log-level: Information
# → info: lines visible, debug: filtered out

[Copilot]

Pull request overview

This PR updates Data API Builder’s dynamic logging control so that MCP agents can reliably override log levels at runtime, establishing the intended precedence order Agent (MCP) > CLI > Config > defaults, and ensuring agent-driven changes are visible through standard logging/notification pathways.

Changes:

• Adjusts DynamicLogLevelProvider so MCP logging/setLevel can override CLI/config-set levels, and prevents hot-reload config updates from clobbering agent/CLI-selected levels.
• Extends ILogLevelController with an IsAgentOverridden flag and updates interface documentation to reflect the new precedence rules.
• Updates MCP stdio handling and unit tests to validate the new precedence and hot-reload behavior.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/Service/Telemetry/DynamicLogLevelProvider.cs	Implements agent-overrides and guards runtime-config hot reload from overwriting agent/CLI selections; emits an audit log on agent changes.
src/Service/Startup.cs	Wires an ILogger into the provider after ILoggerFactory is available so agent override audit logs flow through the normal pipeline.
src/Service.Tests/UnitTests/DynamicLogLevelProviderTests.cs	Updates and adds tests to lock in Agent > CLI > Config behavior, including a hot-reload-after-agent scenario.
src/Core/Telemetry/ILogLevelController.cs	Adds IsAgentOverridden and updates XML docs to match the new precedence contract.
src/Azure.DataApiBuilder.Mcp/Core/McpStdioServer.cs	Reorders notification enabling to ensure the agent override audit log is forwarded to the MCP client.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

[souvikghosh04]

Posted the comments which needs some changes. Approving this assuming those gets addressed.