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

Annotations already cover read/write and idempotency, and the description adds behavioral context beyond that: the ledger is signed and tamper-evident, returns a run_id, and requires an active Bidda subscription via api_key. This is consistent with the annotations, which mark the operation as non-read-only and non-destructive.

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 with the tool's core function, then return value, workflow, and requirement. Every sentence carries useful information without fluff.

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 create-style tool with three params, the description explains the purpose, return value, workflow continuation (record_run_entry, seal_run), and auth requirement. No output schema exists, so noting run_id is sufficient; nothing critical is missing.

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 covers all three parameters with descriptions (100% coverage), including header precedence for api_key. The description adds only a redundant subscription requirement reference, so it doesn't significantly expand on the schema.

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 and resource ('Open a run ledger') and explains the return value (run_id). It clearly differentiates from siblings by outlining the workflow with record_run_entry and seal_run, so an agent can tell it starts a new ledger rather than reading or appending.

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 clear context: use this to start a run ledger for a task/conversation, then use record_run_entry per turn and seal_run to finish. It does not explicitly name alternatives like get_run or state when not to use it, but the workflow makes the intended usage evident.

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