authenticate

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden of behavioral disclosure. It explains the interactive browser window, MFA inclusion, session persistence on an isolated profile, headless reuse, and explicitly states that no PAT or token is stored. This fully discloses the tool's side effects and security posture, going well beyond what the schema or name alone would convey.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences long, front-loaded with the core action and followed by concise usage guidance and behavioral notes. Every sentence earns its place: the first defines the action, the second covers usage frequency and session behavior. No redundant or filler content is present.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple, with one optional parameter and no output schema. The description covers the full context: what it does, when to run it, how authentication persists, and the absence of stored tokens. For an authentication tool, this is complete and leaves no ambiguity about the agent's next steps or the tool's effects.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage for the single parameter (timeoutSeconds) is 100%, with a clear description already in the schema: 'How long to wait for sign-in (default 240s).' The tool description does not add additional meaning about this parameter, so the baseline score of 3 applies. No compensation is needed.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Sign in to Azure DevOps by opening a VISIBLE browser window for interactive login (MFA included).' This uses a specific verb ('Sign in') and resource ('Azure DevOps'), and it is unambiguously distinct from the sibling tools, all of which are read-oriented data retrieval tools. The first sentence fully defines what the tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly says when to use it: 'Run this once (or whenever a tool returns AUTH_REQUIRED).' This is a clear, actionable condition that tells the agent exactly when this tool is needed versus other tools. It also implies when not to run it (when no AUTH_REQUIRED is returned), providing complete usage guidance for this prerequisite auth tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.