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

Goes beyond the annotations by disclosing the auth requirement, that the copy lands as a private draft in your account, and that provenance/proofs are preserved in the copy — meaningful context for a write tool with openWorldHint and non-idempotent semantics. It does not warn that repeated forks create duplicate copies, which the idempotentHint=false implies but leaves unstated.

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?

Two compact sentences, front-loaded with the action and result, followed by eligibility and the auth note. Every clause carries information; nothing is restated from the schema.

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 three-param, fully-described schema with annotations covering safety and mutability, this is nearly sufficient. The one gap is return behavior: with no output schema, the agent isn't told whether the new table's slug comes back, which matters for chaining into add_columns or fill_cells.

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 slug/owner/title are already fully documented with formats and defaults. The description adds nothing parameter-specific beyond the token prerequisite, which is not a schema field. Baseline 3 applies.

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 (copy/fork) and resource (table), the exact result (a private draft in your own account), and the motive (to extend or relabel). It also delineates eligible sources — any published public table or one you run — which separates it from create_table and get_table without opening a 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 condition for use (extend or relabel) plus a source-eligibility rule and a prerequisite ("Needs a token"). It stops short of naming alternatives such as create_table for from-scratch work or save_version for snapshotting, so the routing is clear but not exhaustive.

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