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

Annotations only declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, which leaves the update semantics unexplained. The description fills that gap by stating that only supplied fields change, so omitted fields are preserved, and that is_paused=true halts sending entirely — both non-obvious behaviors an agent needs before calling. It stops short of disclosing permission requirements, whether slug changes break existing page addresses, or whether a paused Nod still answers reads.

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 with no filler, and the partial-update rule is front-loaded where the agent will read it first. The second sentence is narrowly scoped to one parameter, which makes the overall length feel slightly lopsided but not wasteful.

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?

The tool has 12 parameters, annotations that cover only safety hints, and an output schema, so the description carries moderate burden. It covers the essential partial-update contract but omits what the caller gets back, what happens to a Nod when paused (still listed? still reachable?), and whether slug edits invalidate the existing page address.

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 75%, so most parameters (face, brain, voice, slug, abilities, personality) are already documented. The description adds one critical cross-parameter rule — omitted fields are untouched — but singles out is_paused for explicit explanation while the remaining undocumented parameters get nothing extra.

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 never states what a Nod is or that this edits an existing one; that verb+resource information lives only in the name and title. "Changes only the fields you pass" conveys update semantics rather than purpose, so an agent gets partial-update behavior but not a standalone statement of what the tool does.

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?

There is no guidance on when to use this versus create_nod (for new Nods) or get_nod (for reading), and no mention that id is required or that a Nod must already exist. The only usage-adjacent hint is the is_paused instruction, which is parameter-level, not tool-selection guidance.

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