session_read

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

Given no annotations, the description partially discloses behavior by explaining mode auto-detection for TUI applications and diff mode returning only changed lines. However, it does not explicitly state that this is a read-only operation (non-destructive) or mention any side effects, rate limits, or error conditions.

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, front-loaded with the primary purpose, and every clause contributes meaning. No redundant or vague phrasing.

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?

With 6 parameters (some mode-specific) and no output schema, the description is too sparse. It does not explain parameter interactions (e.g., timeout only in stream mode, scrollback only in snapshot), truncation, or return format. More detail is needed to fully guide correct usage.

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 coverage is 100%, so baseline is 3. The description adds value by explaining that 'auto' auto-detects TUI applications and that 'diff' returns only changed screen lines, which is not fully detailed in the schema's parameter descriptions. It does not cover other parameters but that is acceptable given schema completeness.

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 verb 'Read' and resource 'output from a session', defining the tool's core function. It also explains key modes ('auto', 'diff') that distinguish it from sibling tools like session_send or session_create, which handle other session operations.

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 does not provide any guidance on when to use session_read versus alternative tools (e.g., session_list, session_interact). It only describes internal mode behavior, leaving the selection context implicit. No exclusions or prerequisites are mentioned.

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