read_messages

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

No annotations exist, so the description carries the full burden. It discloses the ordering behavior ('most recent first') and the limit semantics, which is genuinely useful, but omits auth requirements, behavior on empty chats, and whether older messages are reachable. An output schema exists, so return format is covered elsewhere.

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?

Two compact sentences plus a lean Args block, with the purpose front-loaded and zero filler. Every line contributes information.

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 two-parameter read tool with an output schema, the definition covers purpose, both parameters, and ordering. It stops short of describing pagination to older messages or behavior when the chat is empty, which would fully round it out.

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 0%, so the description must compensate, and it does: it defines chat_id as a 'numeric dialog id, as returned by list_dialogs' and limit as the max number returned, most recent first. That covers both parameters meaningfully, though no default value is stated for limit.

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?

States a specific verb and resource ('Read the most recent messages from a chat/channel'), making the scope (recent, not filtered) clear. It implicitly distinguishes itself from search_messages by emphasizing recency, but never names the sibling explicitly.

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?

Provides a useful prerequisite by noting chat_id is 'as returned by list_dialogs,' which implies the correct workflow. However, it gives no guidance on when to use this versus search_messages or unread_summary, and no exclusions.

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