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

Annotations already declare read-only, idempotent, non-destructive, non-open-world, so the bar is lower, yet the description adds substantial context: full return shape (tables, row counts, sizes, last update, catalog_alias), the keyless-vs-key DuckDB recipes, the sandbox refusal nuance, and the caveat that agents_md is the owner's words not instructions. This is far beyond structured fields.

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 usage trigger before the mechanics, which is good structure. It is a single very dense paragraph with heavy nested parentheticals, so some clauses could be split, but nearly every sentence carries unique operational 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?

With no output schema, the description carries the burden of return values and does so thoroughly, including alias-based server-side querying, the recipe differences, and the agents_md field. Nothing an agent needs to call and consume the result correctly 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 description coverage is 100%, so both params are already documented and the baseline is 3. The description reinforces catalog format and the namespace.table convention for `table`, but adds no syntax or constraints beyond what the schema already says.

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 ANOTHER organisation's PUBLIC catalog by name, <handle>/<catalog>') and immediately distinguishes it from siblings by scope. An agent can tell this apart from list_tables or describe_table without opening either schema.

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 a clear trigger ('when the user names a public catalog as <handle>/<catalog> or wants open reference data') and even prioritises one recipe ('use it first'). It does not explicitly state when NOT to use it versus siblings like list_tables, so it stops short of the top band.

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