Retrieve session

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the appended 'Read operation' is largely redundant. The description does add useful disclosure that the payload includes messages, state, agent metadata, and participants, but nothing about auth, rate limits, or failure behavior.

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?

Two tight sentences with the primary purpose and returned payload front-loaded and no wasted wording.

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 usefully enumerates the returned content, which is the key missing structured information. It is largely complete for a read-by-ID tool, though it omits error/not-found behavior.

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 100%, so both account and session_id are already documented in the schema. The description reinforces that retrieval is keyed on the ID but adds no syntax or format detail beyond what the schema provides.

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?

States a specific verb (Retrieve) and resource (session) and enumerates what is returned (messages, state, agent metadata, participants), which distinguishes it from list_sessions. It could be sharper by explicitly contrasting with the sibling list_sessions, but the 'by ID' scope makes the difference clear.

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 'by ID' phrasing implies the tool is for when a specific session identifier is already known, but there is no explicit when-to-use routing against alternatives like list_sessions or get_run_details. Usage is merely implied.

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