presentation-add-rendering

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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false), and the description adds genuinely useful behavior beyond them: 'Writes whatever it is told' discloses that no component-validity check is performed, which explains the risk of an invalid layout. It does not mention permissions, index handling, or what happens to existing renderings at the target placeholder.

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 tight sentences, front-loaded with the action and immediately followed by the caution and alternatives. Nothing is repeated from the schema or annotations, and every clause carries decision-relevant information.

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 no output schema but full parameter documentation and annotations, the description supplies purpose, the key behavioral caveat, and routing advice to safer alternatives. Minor gaps remain (layout side effects, index semantics, error behavior), but an agent has enough to invoke 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 100% across all 10 parameters, so the schema already explains id/path, database, finalLayout, renderingId vs renderingPath, etc. The description adds no parameter-level detail of its own, which is the expected baseline when the schema does the work.

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 ('Adds a rendering to presentation of an item'), which is far more than a restatement of the name. It does point at related tools (get-allowed-components-by-placeholder, add-rendering-to-placeholder), but it does not distinguish itself from the nearest siblings such as presentation-set-rendering or presentation-switch-rendering, which also mutate layout.

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?

Explicitly names the safer alternatives and the condition that selects them ('...if the layout has to stay valid'), so the agent knows when this raw-write path is inappropriate. It stops short of stating positively when this tool is the right choice, but the conditional guidance is clear.

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