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

Annotations declare destructiveHint=true, but the description goes well beyond that: partial-update semantics (omitted fields preserved), null-clears semantics per field, the non-clearable name rule, list-replacement semantics for knownBrands, the archived-refusal error code, explicit blast-radius limits (no Client/Site deletion, reassignment or Scan), and retry guidance after an uncertain write.

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?

Long but front-loaded with the action and id source, and every sentence carries a distinct, actionable semantic (partial-update rules, list replacement, archived refusal, blast radius, retry). No filler or restatement of the title.

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 needn't be described, and the remaining complexity (null handling, list replacement, archived refusal, non-deletion guarantees, retry behavior) is all covered. An agent has everything needed to call this mutation correctly and safely.

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%, so the description carries the full burden and does: it explains that null clears websiteUrl, industry or description, that a nonblank name renames and cannot be cleared, and that knownBrands replaces the entire descriptive list (with null/[] clearing it while preserving unrelated metadata). This is exactly the meaning the bare schema types cannot convey.

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 and resource ('Edit one saved Client by clientId') and immediately anchors it against siblings list_clients (source of the id) and get_client (read first). An agent can distinguish it from update_account, update_site, update_topic 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?

Explicit sequencing ('read get_client first'), an explicit precondition ('At least one supplied edit is required'), and an explicit alternative for a conflicting case ('Edits to an archived Client are refused with client_archived; use archive_client for retirement'). When, prerequisites, and alternatives are all covered.

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