get_thread

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

Annotations already declare readOnlyHint=true and openWorldHint=true, and the description adds useful behavior beyond that: newest-first ordering, the channel discussion-group permission requirement, and error behavior for unsupported threads. It does not describe pagination behavior or return shape, but the added constraints are meaningful.

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 short and front-loads the core purpose. The remaining sentences add permission and error context, though the 'thread_root' wording creates avoidable confusion relative to the schema.

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 description establishes purpose, ordering, a permission prerequisite, and error behavior, which is enough for a minimal understanding. However, with no output schema and 0% schema description coverage, it should explain the return shape or pagination and clarify the 'ref' parameter more fully.

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 0%, so the description must carry parameter meaning. It refers to 'thread_root', but the schema parameter is actually 'ref', and it does not explain the string-vs-MessageRef shape, limit semantics, or cursor pagination. The mismatch and missing parameter detail are significant gaps.

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: reading replies to a thread root or comments on a channel post. It also states ordering (newest first) and distinguishes the root fetch from get_messages, so an agent can identify the tool's purpose without opening the schema.

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 clear usage conditions: for channels the linked discussion group must be permitted, unsupported threads return an error, and get_messages can fetch the root. It does not explicitly compare against every sibling such as get_context or get_history, but the primary context is clear.

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