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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful return-content context (author, text, engagement counts, media), but does not disclose edge cases like invalid IDs, missing tweets, or rate limits. Given the annotation coverage, this is acceptable but not rich.

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 with no wasted words. The primary action and input format are front-loaded, followed by a clear use-case rationale. Every sentence adds value, and the structure lets an agent quickly decide whether this is the right tool.

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 single-parameter, read-only batch fetch tool with strong annotations and a detailed parameter description, nothing critical is missing. The description explains what the tool returns, when to use it, and the input constraints, making it fully actionable without an output schema.

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 100%, and the parameter's schema already documents that tweet_ids is a comma-separated string of up to 100 numeric strings. The description essentially repeats this information without adding new parameter-level insight, so the baseline of 3 applies.

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 ('batch-fetch') and a clear resource ('full tweet objects by numeric tweet IDs'), immediately distinguishing it from sibling tools that handle searches, replies, or user timelines. It states the exact input format and the payload contents, leaving no ambiguity about what the tool does.

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 clearly states when to use this tool: 'when you already have specific tweet IDs' and need full tweet data, with concrete examples of where those IDs come from. It does not explicitly name alternatives or state when not to use it, but the guidance is contextually strong enough to prevent confusion with search_tweets or user-centric tools.

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