set_fx_param

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

With no annotations, the description carries the burden and does well: it discloses that writes are undo-block wrapped, that dry_run previews without mutating, and that formatted_value triggers a binary search on the display string. Auth requirements and error/failure behavior are still undisclosed.

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?

Terse, front-loaded, and every clause earns its place: purpose, the three value modes with examples, the scan-first routing, and the undo/dry_run traits, all in four compact sentences.

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 13-parameter mutation tool with no annotations and no output schema, the description covers the critical value semantics and mutation safety, but leaves the targeting parameters (fx_index, fx_scope, name matching) and error/output behavior unexplained.

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 coverage is only 38% across 13 params. The description adds real meaning for the three value parameters (0-1 range, display-string examples, relative syntax) and hints at param_index preference, but fx_index, fx_scope, param_name_contains, and fx_name_contains remain undocumented in both schema and description.

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 ('Set one FX parameter') and clearly delineates itself from the read-side sibling by instructing the agent to scan with get_fx_parameters first. It does not distinguish itself from nearby write siblings like set_fx_preset, tune_param, or write_automation, so it falls short of a 5.

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 an explicit prerequisite and alternative ('Scan with get_fx_parameters first and prefer param_index'), plus three concrete input modes (normalized, formatted, relative). No when-not-to-use guidance against sibling mutation tools, so not a 5.

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