configure_session

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

Discloses that description is free-form and does not affect execution, and explains how shell_prompt_regex is used. However, with no annotations, it lacks details on whether updates overwrite or merge existing settings.

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?

Well-structured with main purpose first, then parameter details. Some redundancy about 'description' but overall efficient.

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?

Covers key aspects: function, parameter usage, and pre-creation capability. Lacks mention of return value or error states, but acceptable given it's a configuration tool.

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?

Adds meaning beyond schema for description and shell_prompt_regex (e.g., regex matched against last visible line). Does not explain session_id parameter, which is required and undocumented in 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?

Clearly states it updates session metadata and shell prompt detection. Distinguishes from sibling tools which focus on input, output, and session lifecycle.

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?

Explains it can be called before a session exists and that values are applied on creation. Provides context but does not explicitly mention alternatives or when not to use.

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