Health check

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint. The description adds specific behavioral details: it opens the composer to inspect but never posts, and discards any draft. No contradictions.

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?

Three sentences, no wasted words. Front-loaded with core purpose, then usage guidance, then behavioral note. Highly efficient.

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 one optional parameter, explicit annotations, and an output schema (mentioned), the description fully covers purpose, usage context, behavior, and parameter semantics. No gaps.

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?

Single parameter 'deep' with 100% schema description coverage. The description adds semantic context by explaining the deeper check ('load real post page and activity feed') and trade-off ('slower, needs a post'). Baseline 3, +1 for added context.

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 the tool's purpose: checking session validity and DOM anchor presence for write tools. It uses specific verbs ('check', 'drive') and resource ('Threads', 'DOM anchor'), and distinguishes from sibling write tools by being diagnostic.

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 ('when tools start failing oddly') and provides context about Meta UI changes. Also clarifies it is read-only and discards drafts, preventing misuse.

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