pty_close

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

With no annotations provided, the description fully carries the behavioral disclosure burden. It reveals that closing destroys logs and read position (destructive side effects), that retries are idempotent and safe, and that the tool returns a structured receipt with states 'closed' or 'already_closed'. This is rich, honest behavioral transparency.

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 long, front-loaded with the core action, and every phrase earns its place. It covers purpose, side effects, retry behavior, and return type without any filler.

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 simplicity (one required parameter) and the presence of an output schema (structured receipt), the description is sufficiently complete. It covers the action, the destructive side effect, the idempotency behavior, and the return format, leaving no major 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?

The schema only defines session_id as a string with no description (0% coverage). The description compensates by explaining that session_id is used for retry safety, and that the same value will yield a receipt indicating whether it was newly closed or already closed. This adds meaningful semantics beyond the raw 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 clearly states the tool's action: 'Close the session and discard logs/read position.' It uses a specific verb ('close') and resource ('session'), and distinguishes itself from sibling tools like pty_open, pty_send, pty_read, and pty_list by focusing solely on the closing 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?

The description implies when to use the tool (to close a PTY session) but does not explicitly contrast it with alternatives or provide exclusion criteria. It adds a safety note about retrying with the same session_id, but lacks explicit 'when to use vs. not use' guidance.

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