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

Annotations already declare readOnlyHint=false, destructiveHint=false and notably idempotentHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond that: it is a per-workspace overlay patch and explicitly does NOT touch shared firmographics, defining the blast radius of the write. It omits partial-failure behavior and whether omitted fields are cleared.

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 sentences, zero waste, with the scope of the mutation front-loaded and the negative scope constraint immediately after. Nothing redundant.

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?

An output schema exists, so return values need not be explained, and workspaceId resolution is fully covered by the schema description. For a bounded mutation tool the description covers resource, field scope, limits and non-effects; only edge-case semantics (partial failure, clearing fields) are absent.

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 50%: workspaceId is richly documented in the schema while the nested companyId/tags/notes items have no descriptions. The description names the patchable fields and the 50-item cap (the cap is already in the schema as maxItems), so it adds mild clarification rather than compensating for the undocumented nested fields.

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 (patch) and a specific resource (per-workspace company overlays), and clarifies the exact mutable fields (tags/notes) plus the blast radius (not shared firmographics). It is clearly separable from get_companies, refresh_companies and enrich_companies, though it does not name a sibling explicitly.

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?

Usage is implied by the scope statement (edit tags/notes on up to 50 companies), and the negative clause 'does not mutate shared firmographics' nudges the agent toward other tools for firmographic changes. However, there is no explicit when-to-use/when-not or named alternative, so guidance stays at the implied level.

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