@git-fabric/chat

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes key traits: it creates a new session (implying a write operation), preserves history up to a point, and leaves the original unchanged. However, it omits details like permissions needed, rate limits, or error conditions, which would be helpful for a mutation tool.

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 the core purpose in the first sentence, followed by essential behavioral details in two concise sentences. Every sentence adds value without redundancy, making it efficient and easy to parse for an AI agent.

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 (a mutation operation with 3 parameters), no annotations, and no output schema, the description is adequate but incomplete. It covers the basic purpose and behavior but lacks information on return values, error handling, or deeper context like how the forked session integrates with other tools. It meets minimum viability but has clear gaps.

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%, so the schema already documents all three parameters (sessionId, forkFromMessageId, title) with clear descriptions. The description adds no additional parameter semantics beyond what the schema provides, such as explaining the relationship between sessionId and forkFromMessageId or title defaults. Baseline 3 is appropriate as the schema does the heavy lifting.

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 states the specific action ('Fork a session at a specific message'), the resource involved ('session'), and the outcome ('Creates a new session with all history up to and including the fork point'). It distinguishes this tool from siblings like chat_session_create by specifying it creates a copy from an existing session at a particular point, not a blank session.

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 context ('to explore an alternative branch of conversation') but does not explicitly state when to use this tool versus alternatives like chat_session_create or chat_session_get. It mentions the original session is unchanged, which helps differentiate from destructive operations, but lacks clear guidance on prerequisites or exclusions.

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