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

Annotations already declare non-read-only, non-destructive, idempotent, closed-world behavior, so the safety profile is covered. The description usefully adds that saved searches are 'private' and that it pairs with search for change notifications, but says nothing about permissions, ownership, or what happens to a prior version on update (schema covers retry semantics via op_key).

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 short sentences, zero filler, with the core create-or-update action front-loaded before the follow-up workflow hint.

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 full schema coverage and annotations covering idempotency and destructiveness, the description supplies the missing pieces: privacy scope and the search follow-up pattern, with no output schema to explain. Minor gap around permission requirements keeps it from a 5.

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%, including the nested criteria object, op_key retry semantics, and expected_version create/update logic, so the schema carries full parameter burden. The description adds no parameter-level meaning beyond that, making the baseline 3 appropriate.

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 pair and resource ('Create or update a private saved search'), which clearly separates it from read-only siblings like list_saved_searches and run_search. It also flags the upsert semantics and the private visibility scope. It stops short of explicitly naming the sibling tools it competes with.

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?

'Follow it with type search to receive matching changes' gives a usage flow, implying this tool is a setup step paired with search. However, it never states when to prefer this over alternatives, nor explains the update-vs-create decision beyond what the schema's id/expected_version fields already imply.

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