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

With no annotations provided, the description carries the full transparency burden. It discloses idempotency ('CREATE TABLE IF NOT EXISTS'), harmlessness on success, restricted operator access requiring nsec-signed proof, per-step result returns, and inline error surfacing behavior—all beyond what the schema reveals.

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 organized into four paragraphs, each addressing a distinct aspect: action, use case, idempotency/behavior, and access restriction. It is somewhat verbose (e.g., the 0.31.0 error-body detail) but every sentence contributes useful 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?

The description fully covers purpose, trigger conditions, safety profile, return behavior, error handling, and authentication requirements. With an output schema present, it need not explain return shapes in detail; the provided context is enough to safely invoke the tool.

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 0%, and the description does not mention dpop_token at all. The sole parameter remains unexplained beyond its name and default value. The description's mention of 'nsec-signed' proof hints at authentication but does not connect it to dpop_token, leaving a semantic gap.

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 uses a specific verb+resource: 'Re-run ensure_schema() on every NeonVault this operator uses.' It clearly identifies the tool as a diagnostic/recovery mechanism for persistent 4xx Neon HTTP SQL API errors, which distinguishes it from sibling tools like brain_scan_orphans or brain_service_status.

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 explicitly states when to use it: 'persistent 4xx errors and the operator suspects the schema isn't there or grants are wrong.' It provides a clear context for invocation but does not name alternatives or exclusion criteria, so it falls slightly short of a 5.

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