get_thread

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

With no annotations provided, the description carries the burden of behavioral disclosure. It states that the tool returns every message in a thread, enforces oldest-first ordering, and requires the filtering parameters to match the originating view. This is meaningful behavioral context beyond basic schema information.

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 tight sentences with no wasted words. The core behavior is front-loaded, and the important filter-matching guidance appears immediately after.

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 list tool with no output schema and no annotations, the description gives enough context to call it correctly: the resource scope, ordering, and the relationship between optional parameters and the originating view. Required parameters are well-covered in the schema. Minor gaps remain around the return shape, but they are not critical for invocation.

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 only 40%, so the description must compensate. threadKey and mailbox are already described in the schema, and the description adds that direction/trash/folder should mirror the view where the thread was found. However, the individual semantics of these optional parameters remain somewhat underspecified.

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 uses a specific verb and resource: 'List every individual message in one thread, oldest first.' It clearly distinguishes from the sibling get_message by describing thread-level scope rather than a single message, and adds ordering behavior.

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 instruction to 'Pass the same direction/trash/folder as the view you found the thread in' provides clear contextual guidance for the optional parameters. It does not explicitly contrast alternatives, but the usage context is clear enough for an agent to know when to call this tool.

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