read_message_range

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

With no annotations, the description carries the full burden. It discloses key behaviors: inclusive start_seq, exclusive end_seq, 500-message maximum, and agent_id session membership. It does not describe error cases or return format, but for a read-only range retrieval tool the coverage is solid.

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 front-loaded with a one-sentence summary, followed by scannable trigger bullets and a compact parameter list. No filler or redundant content; each section earns its place by helping selection or invocation.

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's moderate complexity and absent output schema, the description covers purpose, triggers, sibling differentiation, and all parameter semantics. It does not explicitly describe the return shape, but 'Read messages' clearly implies the returned content, and nothing needed to select or invoke the tool is missing.

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%, but the inline PARAMETERS section fully compensates. Every parameter gets meaningful guidance: start_seq should come from message metadata, end_seq is exclusive with a max range of 500, and agent_id must belong to the session. This adds significant value beyond the bare schema.

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 opens with a specific verb and scope: 'Read messages in a specific sequence range'. It clearly distinguishes itself from read_messages by focusing on range-based retrieval rather than 'new' messages, so an agent can differentiate it from related message tools.

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 'AUTOMATIC TRIGGERS' section explicitly lists when to call the tool (e.g., 'A message references an earlier seq number', 'review a specific exchange between agents'). It also names the alternative read_messages and explains the difference, giving clear when-to-use and when-not-to-use guidance.

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