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

Annotations already indicate readOnlyHint=false and idempotentHint=false, and the description adds relevant context: a new ledger is opened, a run_id is returned, and an active Bidda subscription is required. This goes beyond what the annotations alone communicate and does not contradict them.

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?

The description is compact and front-loaded, beginning with the action and core resource definition. Every sentence supplies a distinct, useful fact: purpose, return value, subsequent workflow steps, and authentication requirement — with 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 tool with one required parameter and no output schema, the description covers the return value, the subscription requirement, and the surrounding workflow. It could additionally clarify whether opening always creates a new ledger versus reopening one, but the essential calling context is present.

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 the schema already documents agent, label, and api_key. The description adds only general context about api_key being the subscription key; parameter-specific semantics are otherwise already present. This is the appropriate 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 states a specific action and resource: 'Open a run ledger' and defines it as a signed, tamper-evident log across a whole task or conversation. It also says the tool returns a run_id and distinguishes itself from workflow siblings by explicitly placing it as the first step before record_run_entry and seal_run.

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 gives lifecycle guidance: open a ledger, record one entry per turn with record_run_entry, then seal_run to obtain a receipt. It does not explicitly state when not to use this tool or contrast it with get_run and related lookup tools, but the workflow context is clear enough for an agent to pick the right step.

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