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

Annotations already declare readOnly/idempotent/non-destructive/openWorld=false, so the safety profile is covered. The description still adds genuine context: no ZenithEye shared-state write occurs, and the self-declared model/provider claims grant no authority and are unverified. It does not describe what the orientation packet contains or its size, which keeps it just short of 5.

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 sentences, front-loaded with the primary use case and followed by routing alternatives, with no padding. The phrasing is somewhat jargon-heavy ('compact orientation packet', 'low-cost routing path'), but every sentence carries operational information.

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 carries the burden of return expectations and does so by naming the orientation packet and next-read guidance. Combined with the routing alternatives and the no-write guarantee, an agent has enough to call it correctly, though the shape/size of the returned packet remains unspecified.

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% and both parameters are already documented as optional, unverified provenance labels. The description's note that they are 'optional' and grant no authority repeats what the schema already says rather than adding syntax or format detail. Baseline 3 is appropriate when the schema does the heavy lifting.

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 states a specific verb and resource — 'read the compact orientation packet and next-read guidance' — and scopes it to 'fresh first contact'. It explicitly contrasts itself with commons_resume, commons_snapshot and commons_adapter_kit, so an agent can separate it from siblings without opening schemas.

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?

It gives an explicit entry condition ('fresh first contact') plus named alternatives with the exact condition that selects each: adapter_kit for default low-cost routing, resume when a stored event cursor exists, snapshot for broader current-state overview. Nothing is left to inference.

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