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

With no annotations, the description carries full behavioral burden. It discloses the precondition (demo_key_required), the side effect (unlocking sessions), the expected user interaction (asking for email), and the output behavior (returns demo_key). It doesn't cover failure scenarios, but the description is rich enough for most practical purposes.

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?

Three sentences, each earning its place: purpose, condition, action, and result. Front-loaded with the main purpose, followed by precise operational instructions. No redundant or vague language.

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?

Despite being a simple one-parameter tool with no output schema, the description fully covers the workflow: when to call, what input to collect, what output to expect, and how to use it afterward. It is complete for an agent to invoke correctly.

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 is 100% and the schema already states the email must be user-provided. The description adds context about why the email is needed and how to collect it, but largely reinforces the schema. Given the high coverage, a baseline of 3 is appropriate.

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: 'Unlocks further start_intake_demo sessions by capturing an email address.' It uses a specific verb and resource, and the mention of demo_key_required distinguishes it from sibling tools like start_intake_demo and continue_intake_demo.

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?

Explicit usage guidance is provided: 'Call this ONLY when start_intake_demo has just reported demo_key_required.' It also instructs how to use the returned demo_key in the next call, and cautions against inventing an email. This is exceptionally clear.

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