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

Adds critical behavioral details beyond annotations: variable_mapping REPLACES the whole mapping, no re-submission to Meta so no re-approval needed, and returns the updated template row. These are not in the annotations and materially affect how an agent invokes it.

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 description is dense but efficient, front-loading the purpose and then layering critical constraints. A few extra clauses (e.g., 'e.g. it said "Hi Alex"...') add clarity without bloat, though it could be slightly more compact.

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, it covers the purpose, the replacement semantics, the value formats, the no-reapproval implication, and a suggested follow-up. Nothing essential for correct invocation is missing.

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 100%, but the description adds meaning: for variable_mapping it explains the whole-replacement behavior, requires an entry per placeholder, gives an example, and clarifies value formats (top-level vs fields.<key>). This goes well beyond the schema's generic 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?

The description states a specific verb (wire) and resource (template placeholders to contact fields), and provides a concrete scenario (fixing blank/wrong values) that makes its purpose unmistakable. It clearly distinguishes itself from template creation/update by focusing on mapping placeholders, not content.

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?

It gives clear context: use this when a broadcast went out with a blank or wrong value, and advises preview_broadcast afterward. It doesn't explicitly name alternatives like update_template, but the use case is strong enough to guide selection.

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