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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety profile is covered. The description adds meaningful behavioral context beyond annotations: the four possible return states and what 'waiting' means ('nobody logged on yet'). This is exactly the kind of semantic detail annotations cannot express.

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: the question front-loads the purpose, and the enumeration of return states is compact and immediately useful. No 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?

For a single-parameter read-only status check with no output schema, the description supplies the essential missing piece – the set of possible states. It does not explain how to obtain a valid sessionId or how quickly state transitions occur, minor omissions for this complexity level.

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 0%, so the description could carry more load, but with only one required uuid parameter named sessionId the gap is minor. The description implies the query is scoped to a session but does not clarify the sessionId format or source. Baseline 3 given the single trivial parameter.

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 (check) and resource (sandbox connection status) framed as a question ('Is the user's FIX engine connected to the sandbox session?'). Clearly distinguishable from siblings like sandbox_get_session (session metadata) or sandbox_get_orders. Missing explicit sibling differentiation in text, but purpose is unambiguous.

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 is implied by the name and the framing question – an agent would use this to poll connectivity. No explicit when-to-use versus when-not-to-use, and no mention of alternatives such as sandbox_get_session. Adequate but leaves routing to inference.

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