terminal_snapshot

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

Beyond the readOnlyHint annotation, the description adds meaningful behavioral detail: 'settleMs:0 captures without a quiet wait' and 'An exited process keeps its final screen until the session is closed.' These reveal timing and lifecycle behavior an agent could not infer from annotations alone.

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?

Three sentences with no filler: the main purpose is front-loaded, then scrollback scope, then the two behavioral exceptions. Every sentence adds information needed to call the tool correctly.

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?

The description covers the tool's content (screen, styles, cursor, process status), optional scrollback, quiet-wait behavior, and exit-state behavior. Since there is no output schema, exact return formatting is left unspecified, but an agent has enough context to invoke the snapshot correctly and interpret its purpose.

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 0%, so the description must compensate. It does explain scrollbackLines ('up to 2,000 normal-buffer scrollback lines') and settleMs ('0 captures without a quiet wait'), but settleTimeoutMs is never mentioned and sessionId is only inferable from its name and required status. This is partial but not complete compensation for the absent schema descriptions.

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 opens with a specific verb and resource: 'Observe the current terminal screen, styles, cursor, and process status without sending input.' This clearly distinguishes the tool from siblings like terminal_input (sends input) and terminal_list (lists sessions), and it names the core read-only operation precisely.

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 by emphasizing 'without sending input' and by explaining optional scrollback and settle behavior, but it never explicitly names alternatives, excludes them, or states conditions such as 'use this instead of terminal_input when you need to inspect state.' Usage context is present but left to inference.

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