get_thread

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

Annotations already mark readOnlyHint=true. The description adds value by explicitly stating 'SIDE EFFECTS: none (does not mark as read)', which confirms no state changes beyond what annotations imply. No contradiction.

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?

Extremely concise: two sentences plus usage notes. Every sentence is purposeful, front-loading the action and key details. No wasted words.

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?

Given the presence of an output schema for return values and readOnlyHint annotation, the description is largely complete. However, failing to explain the 'full' parameter slightly detracts from full parameter coverage, so score 4.

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?

With 0% schema description coverage, the description must compensate but only explains the threadId parameter implicitly. The 'full' boolean parameter with default true is not mentioned, leaving its purpose unclear. Still, threadId is clearly conveyed, so score 3.

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 'Fetch a full thread by ID' and enumerates the returned content (headers, bodies, attachments). It distinguishes from siblings by specifying it takes thread IDs, not message IDs, setting it apart from tools like mark_read or search.

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?

Explicitly states when to use: 'reading a thread's content after finding it via search', and when not to use: 'with a message ID — this takes thread IDs'. Provides clear usage context without needing to reference sibling tool names.

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