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

Annotations already cover the safety profile (readOnlyHint=true), so the description only needs to add operational context. It does: it discloses permission scoping ("tables you may read") and the exact shape of results in both modes, which matters since there is no output schema. No auth or rate-limit caveats are mentioned.

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?

Three front-loaded sentences that each carry unique information: purpose, default behavior, parameterized behavior, and the call-ordering rule. No filler or repetition of the title.

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?

A single optional parameter, no output schema, and the description covers purpose, both return shapes, permissions scope, and when to invoke it. Nothing an agent needs to call this 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 coverage is 100%, so baseline is 3, but the description adds real meaning beyond the schema: omitting `tables` yields a one-line summary of every readable table, while supplying it yields full column lists, types, foreign keys and notes. That mode-switching behavior is not evident from the schema alone.

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 ("Describe the workspace's data tables you may read") and immediately distinguishes itself from the SQL-execution sibling via "Call this before writing SQL." The two output modes are spelled out, so an agent knows exactly what the tool yields in each case.

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?

"Call this before writing SQL" gives a clear when-to-use condition that maps onto the run_sql/dispatch_query siblings. It stops short of naming an alternative explicitly or stating when not to call it (e.g. for non-SQL tasks), so it is strong context rather than a full routing rule.

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