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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds little beyond that: it does not say whether the provided list replaces the existing set or appends to it, what happens to leads from de-selected platforms, or whether site/project scope is required. 'Set' hints at replacement, but that is left implicit.

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?

A single front-loaded sentence with no filler. It is efficient, though the terseness borders on under-specification for a three-parameter mutation rather than being optimally concise.

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, zero parameter documentation, and only bare safety annotations, the description omits too much: scope requirements, replace-vs-append semantics, and any effect on existing leads. It is not sufficient on its own for an agent to call this confidently.

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 0% and all three parameters (projectId, siteId, platforms) are undocumented in the schema. The description names only the platforms concept and says nothing about projectId/siteId scoping or that platforms is a bounded list of up to 10 enum values, so it does not compensate for the coverage gap.

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 clear verb and resource: setting which platforms are searched for leads. An agent can tell this configures lead-source platforms, though nothing distinguishes it from nearby siblings like update_lead_monitor, update_lead_icp, or run_lead_scan.

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?

No when-to-use guidance, no prerequisites, and no mention of alternatives among the many other lead-related update tools. The agent must infer that this is the configuration step for scan sources.

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