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

Annotations cover the safety profile (not read-only, open-world, idempotent, non-destructive), and the description adds real context beyond them: TLS/password still required, propagation 'live within about 30 seconds', and the partial-update semantics of an omitted `sources`. It does not describe failure modes or interaction with existing firewall rules, keeping it from a 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?

Front-loads the core action in the first clause and every sentence carries information (security, sources semantics, timing, scope). Slightly dense with parentheticals, but no wasted sentences.

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 mutation tool with no output schema and only three params, the description covers safety implications, propagation timing, and parameter edge cases well. It lacks any statement of the return value/confirmation or error conditions, a minor gap.

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 coverage is only 33% (only `database` documented), so the description must compensate — and it does, spelling out `sources` values (addresses/ranges, omitted = leave as is, null or [] = everyone) and what `enabled` toggles. It omits the 50-item cap and address string format, so not a 5.

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 (opens/closes) and resource (database public access at its public host and port), including the protocol family (IPv4/IPv6) and what remains in force (TLS and password). This clearly separates it from firewall siblings like attach_firewall or set_rules.

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?

Gives useful guidance on the `sources` parameter ('Prefer listing the user's addresses') and the omitted vs null vs [] behaviors, but never says when to use this versus attach_firewall/set_rules or what prerequisites (auth scope network.write is stated) are needed. Usage context is implied rather than contrasted with alternatives.

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