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

No annotations are provided, so the description carries the full burden. It discloses the reply structure (carries inbox_count) and a side effect of the action (opens/refreshes session), but it does not explain whether the operation is idempotent, what other reply fields exist, or any authentication or rate limits. The disclosure is useful but not comprehensive for a state-changing tool without annotation support.

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 sentences with no filler. The primary purpose is stated first, and the conditional routing to inbox is a necessary second clause. Every word earns its place, and the description is front-loaded with the action and object.

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 tool has one parameter with nested objects and no output schema, so the description must explain the return value. It does mention inbox_count and the conditional follow-up, but it does not explain other potential reply fields, error conditions, or what constitutes a successful handshake beyond the count. For a session-initiation tool, it leaves out what the agent should do if inbox_count is zero or if the handshake fails. Completeness is adequate but not thorough.

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 reported at 100%, so the schema already documents the envelope and focus parameters with descriptions. The description adds context about the envelope being 'your context envelope' and that the query IS the context, which is a conceptual framing rather than new parameter semantics. It does not add syntax, format, or examples beyond what the schema provides, so it stays at the 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 clearly states the tool's purpose: 'Open/refresh your pair session: send your context envelope across the input boundary (registered pairs).' It names a specific action (open/refresh) and resource (pair session), and differentiates from at least one sibling by routing to pairgora_inbox conditionally. However, it does not explicitly distinguish itself from other siblings like pairgora_join or pairgora_store, so it stops short of full differentiation.

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 provides one explicit usage directive: 'if it is not zero, call pairgora_inbox next,' which tells the agent when to chain to a sibling. It also implies the tool is used to initiate or refresh a session. However, it does not state when to use handshake over other session-related tools (join, store) or when not to use it, leaving the selection partially to inference.

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