subscription_errors

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

Discloses that it reads pg_stat_subscription_stats, is deterministic, and runs on the subscriber. Notes that non-zero apply_error_count indicates a wedged subscription. No annotations provided, so description carries full burden; additionally stating that it's read-only and has no side effects would raise this to 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?

Extremely concise: three short sentences cover purpose, characteristics, data source, practical significance, and run location. Every sentence adds unique value with no redundancy.

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 zero parameters and an output schema, the description fully covers purpose, source, location, and interpretation of results. Nothing essential is missing given the tool's simplicity.

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?

No parameters exist, so description adds no param-specific info, but that's appropriate (baseline 4). The description focuses on the tool's function and output, which is sufficient.

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 it reports apply and tablesync error counts per subscription, names the specific system view (pg_stat_subscription_stats), and distinguishes from siblings by focusing on error counts. The verb 'report' and resource 'error counts' are explicit.

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?

Provides clear context: run on the SUBSCRIBER, deterministic, reads PG15+ stats, and hints at use case (first sign of wedged subscription). Lacks explicit comparisons to siblings or when-not-to-use, but the sibling set suggests alternative diagnostics.

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