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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is covered. The description adds real context beyond that: the whole body is replaced (not patched), the document must be an existing authorized and non-deleted file, and the write is guarded by a native revision. It omits how authorization is checked and how the idempotency/key behavior works.

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?

A single front-loaded sentence with the core action first, followed by the concurrency precondition and the exclusion. No filler, no repetition of the title or annotations.

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?

This is a destructive mutation with five required parameters at 0% schema coverage, and the description documents only the revision and the deleted-file precondition. It says nothing about request_key/idempotency, the roles of series_id and document_id, or what happens when the revision is stale, leaving an agent under-equipped to call it correctly.

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 0% across five required parameters, so the description carries the full burden. It only glosses two of them ('body' by implication, 'expected_revision' via 'exact native revision'); series_id, document_id, and especially request_key (apparently an idempotency key) are left completely unexplained.

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?

The description names a specific verb and resource: 'Replace an existing ... Series document body,' which is distinguishable from the many generic document siblings (replace_studio_document_body, native.replace_document_body) by the 'Series' qualifier. It does not explicitly name those siblings, so the differentiation is implicit rather than stated.

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?

'using its exact native revision' tells the agent this is an optimistic-concurrency update that requires a fresh revision token, and 'do not recreate a deleted file' is an explicit when-not-to-use rule. It stops short of pointing at an alternative tool for the recreate case or stating what to do on a revision mismatch.

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