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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description still adds value beyond them by disclosing sort order ('newest first') and the exact payload shape, which matters because there is no output schema. It does not mention pagination or behavior when the user has no threads.

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 sentences, zero filler. The scope and ordering come first, and the follow-up pointer to get_thread is appropriately placed at the end as a next-step hint.

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?

For a no-required-param list tool with no output schema, the description compensates by enumerating the returned fields and sort order. Nothing an agent needs to select or call this tool is missing.

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% and the single parameter is fully documented in the schema, including default and min/max. The description adds nothing about limit beyond the schema, so the baseline of 3 applies.

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?

States a specific verb and resource ('List the user's most recent Framevine threads') and defines the resource parenthetically ('conversation-like canvases of generations'), which is genuinely useful for a domain-specific concept. It also enumerates the fields returned, so the agent knows exactly what distinguishes this from list_recent_generations or list_folders.

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 closing sentence gives a clear follow-up path: 'Use a thread id with get_thread to see its contents,' which implicitly tells the agent this tool is a discovery step, not a content reader. It stops short of explicitly naming conditions for when-not to use it versus siblings like list_recent_generations or favorite_thread.

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