session_start

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

There are no annotations, so the description carries the full disclosure burden. It clearly discloses that calling this tool opens a tracked session and that failed steps can fall back to asking the human. It does not mention whether an existing session is replaced or what the function returns, but the main stateful behavior is transparent.

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 two sentences with no filler: one defines what the tool does, and the other gives the usage boundary. It is well structured and front-loaded.

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 session-start tool with two required parameters, the description sufficiently explains its purpose, inputs, and applicability. The main omission is return-value or reentry behavior, but the schema and sibling session tools provide enough surrounding context.

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 parameters are already fully documented. The description adds only the framing that steps are ordered, which reinforces rather than extends the schema. This matches the baseline of 3.

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 action and resource: 'Open a debugging session with a goal and an ordered list of steps.' It also distinguishes the tool from lighter-weight investigations by explaining that it tracks progress and supports fallback to asking the human.

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?

Explicit usage guidance is present: 'Use it for multi-step reproductions; a single-question investigation does not need it.' This clearly tells the agent when to invoke the tool and when to skip it.

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