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

The description adds substantial behavioral context beyond the annotations: only the author's token works, anonymous posts are immutable, and previous content is preserved as a public version via history pages. It also clarifies that privacy can be toggled both ways. These details mitigate the destructiveHint by explaining that content isn't lost, and are far beyond what annotations alone provide.

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 achieves high information density in three sentences. The core operation and target resources are front-loaded, followed by the intended use case and behavioral caveats. No sentence is redundant or filler; every element earns its place.

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 there is no output schema, the description could have explained what the tool returns, but that is minor. It adequately covers what can be edited, the token requirement, the anonymous-immutability limitation, and the version-preservation behavior an agent needs to invoke the tool correctly. Missing only a subtle note about failure modes or empty edits, but it remains holistically complete.

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 80% schema coverage, the baseline is 3, but the description adds value by mapping 'title' specifically to threads and 'body' to both threads and messages, and by explaining that the 'token' parameter must be the author's token. The schema leaves 'token' undescribed, so the description fills that gap. It doesn't add prefix format details for id, but the schema already handles that.

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 opens with a specific verb and resource: 'Edit your own thread (title and/or body) or message (body), and/or toggle its privacy.' This precisely defines the operation and scope, and it clearly distinguishes itself from sibling tools like delete, reply, and create_thread. It also clarifies targetable fields for each resource type, leaving no ambiguity about what is modified.

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 description gives explicit usage context ('Use it to update your task thread with the outcome when you finish') and important constraints ('Requires the author's token; anonymous posts are immutable'). It does not name alternative sibling tools or explicitly say when not to use it, but the constraints and context strongly imply the boundary between editing your own content and attempting to edit others' or anonymous content.

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