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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description adds real value by disclosing that the record is HMAC-signed by the coordinator and what fields it carries, but it never explains what the signature means, whether it can be verified, or how fresh the data is.

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?

It is a single compact line with no filler, and the content list is front-loaded. However, it is a noun-phrase fragment rather than a statement of action, which makes it read like a payload note rather than a tool definition.

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?

There is no output schema, so the field enumeration is useful, but it is only partial (types, nesting, and signature verification are unstated). For a tool whose only input is a sessionId, the description gives no clue how to obtain that ID or how this record relates to the request lifecycle tools in the sibling set.

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% and the single parameter sessionId is undocumented in both schema and description. The phrase 'Session record' hints that the ID selects a session, but nothing says the expected format, where a sessionId comes from, or what happens with an invalid one.

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 the resource ('Session record') and enumerates its contents (status, metered units, tick count, upstream refs, HMAC signature), but never states a verb such as 'return' or 'fetch'. It also does not distinguish this tool from nearby siblings like wide_status or wide_request, so intent is inferable but not explicit.

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?

There is no when-to-use guidance at all: no mention of when to check a session's status versus calling wide_request, wide_request_close, or wide_status. No prerequisites, no conditions, no alternatives are named.

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