Create a DSH session

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

Annotations already declare it is a non-read-only, non-destructive, non-idempotent operation. The description adds real behavioral context beyond that: cwd is path-validated and realpath-canonicalised before use, and model/reasoning_effort are gated by bridge allowlists. It does not cover failure modes or what is returned, but for a creation tool this is solid added value.

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 tight sentences, front-loaded with the operation and followed by the validation rules. There is no filler or restatement of the tool name.

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 no output schema, the description should indicate what a caller gets back (for example a session id needed for dsh_send_message or dsh_close_session) and whether sessions persist until closed. Those gaps are notable for a session-creation tool, though the validation rules are complete.

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 the baseline is 3, but the description adds constraints the schema does not state: the allowlist requirement for cwd and the realpath canonicalisation step. These are meaningful semantics for the most important parameter, lifting it above baseline.

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 names a specific verb and resource ('Create a fresh persistent DSH session') plus the underlying call ('ACP session/new'). The word 'fresh' implicitly contrasts with dsh_resume_session, but no sibling is named explicitly, so differentiation is only partly achieved.

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?

Usage context is implied by 'fresh' versus the sibling dsh_resume_session, and preconditions are stated, but there is no explicit statement of when to prefer this over resuming or how it relates to dsh_list_sessions. The agent must infer the routing rule.

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