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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds mode-behavior context but says nothing about return format, whether generated content is saved or ephemeral, or how interview_notes are parsed. With annotations carrying the safety burden, this is adequate but not rich.

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?

Two compact sentences with the mode concept front-loaded and no filler. The second sentence efficiently maps the two modes to their conditions, though the capitalized 'DISCOVERY MODE' adds slight emphasis noise.

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?

With no output schema but full schema description coverage, the description supplies the key missing behavioral framing (the two operational modes) an agent needs to call correctly. It is nearly complete for this tool, lacking only minor detail on how raw interview_notes are handled.

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 description coverage is 100%, so the schema already documents all nine parameters including the mode enum's meaning and the full-mode requirements. The description reinforces the mode distinction but adds no syntax, format, or edge-case detail beyond what the schema provides, so baseline 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 states a specific verb ('Generate') and resource ('case studies') and names its distinctive DISCOVERY MODE. It is clearly distinguishable from siblings like testimonial_capture or newsletter_builder, though it doesn't explicitly reference any sibling by name.

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?

It gives a clear conditional for choosing between the two modes: 'If you have the full story, get a complete case study. If not, get interview questions to gather the story first.' This is genuine usage guidance, though it doesn't address when to prefer this tool over adjacent siblings like testimonial_capture.

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