set_pcg_graph_parameter

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

Annotations cover the safety profile (readOnly=false, idempotent=true, destructive=true), and the description adds substantial context beyond them: it accepts only a PCGGraph asset and errors with 'PCG graph not found' for a PCGGraphInstance, and changing a parameter does not update the world. It even discloses the self-oracle read-back behavior.

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?

The write action is front-loaded, and each sentence carries distinct actionable content (type constraint, asset-only limitation, world-update caveat, return shape). It is dense and slightly long, but no sentence is filler.

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?

Since there is no output schema, the description usefully spells out the return shape { pcg_graph_path, name, type, set, value }. Combined with the asset-only limitation, type matching, and the regeneration requirement, an agent has everything needed 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% so the baseline is 3, but the description adds the accepted value types (bool/int/float/double) and the type-must-match constraint, clarifying the 'value' parameter beyond the schema. The pcg_graph_path naming and asset-vs-instance distinction are reinforced in prose.

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+resource (write the value of an existing PCG graph user parameter) and explicitly scopes it against siblings like add_pcg_graph_parameter and the parameter read path. An agent can distinguish it from get_pcg_graph_parameters and add_pcg_graph_parameter without opening any 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 explicit preconditions (parameter must already exist via add_pcg_graph_parameter, value type must match) and the exact follow-up workflow (cleanup_pcg_component then generate_pcg_component) needed for the change to take effect. It also states the exclusion (PCGGraphInstance not supported; per-instance overrides must be ticked in the details panel).

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