zalo_read_messages

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

No annotations are provided, so the description bears full responsibility for disclosing behavioral traits. It states the tool reads messages (implying a read-only operation) but does not clarify side effects, permission requirements (e.g., OAuth scopes), or limits like message count or time range for 'recent'. The dependence on being 'linked' is vague.

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 a single sentence that is concise and front-loaded. However, it could be slightly improved by clarifying the 'captured' and 'linked' concepts, which would reduce potential confusion without significantly increasing length.

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 no output schema and no annotations, the description should provide more context. It lacks information about the return format (e.g., message content, sender, timestamps), pagination, or error conditions. For a simple read tool with no parameters, it is minimally adequate but leaves gaps for an AI agent to make assumptions.

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 input schema has zero parameters and 100% schema description coverage. With no parameters to document, the description naturally adds no parameter details, but the baseline of 4 is appropriate. The description implicitly confirms that no user input is required beyond invoking the tool.

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 specifies the verb 'reads' and the resource 'recent Zalo messages', and it differentiates from sibling tools like 'zalo_list_chats' (lists chats, not messages) and 'zalo_search_messages' (searches for specific messages). However, the phrase 'that Local MCP captured while linked' introduces some ambiguity about whether messages are stored locally or fetched in real-time.

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?

No guidance is provided on when to use this tool versus alternatives. With siblings like 'read_messages' (generic), 'zalo_search_messages', and 'signal_read_messages', the description does not explain the specific use case or prerequisites (e.g., needing an active Zalo connection or prior capture). The agent must infer context from the tool name alone.

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