get_activity_messages

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

No annotations are provided, so the description carries the full burden. It discloses the pagination cap (at most 100 messages), the read-only nature ('this read'), the guarantee that empty lists are possible but members are objects, and that content is untrusted with a fingerprint that does not replace original content. This adds valuable context beyond the schema.

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 three sentences, front-loaded with purpose, and avoids fluff. It packs significant behavioral detail efficiently, though the caveats could be tightened, but overall it is well-structured and concise.

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 tool has two parameters and an output schema, the description covers the core purpose and some behavioral quirks, but it omits any parameter guidance and does not clarify when to use it. The output schema handles return structure, but the lack of parameter semantics leaves an incomplete picture for a read tool.

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?

The description does not mention either parameter (api_key or activity_id) at all. Since schema description coverage is 0%, the description should compensate by explaining parameter roles or constraints, but it offers nothing, leaving the agent to infer from schema titles alone.

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 states a specific verb ('Return'), a clear resource ('upstream activity-message list'), and the key property of preserving text and identity metadata. This clearly distinguishes it from sibling tools like get_activity_details or get_activity_streams, which target different data.

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 implies usage by naming the resource, but it does not explicitly state when to use this tool versus alternatives or provide exclusion conditions. It only gives a limitation about pagination, not guidance on selection.

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