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

Annotations only flag readOnlyHint=false and openWorldHint=false, so the description carries the interesting behavior — and it does: this is an upsert keyed by name (creates or edits), secret constants cannot have their value set via API/MCP, and the secret flag is effectively one-way. These are non-obvious operational traits an agent would otherwise learn only by failing.

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?

Three compact sentences with the action front-loaded, then the value requirement, then the secret caveat. Wording is efficient, though the secret-value rule is partly repeated in the schema's value description, so it is not maximally tight.

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 5-parameter mutation with no output schema, the description covers what an agent needs to call it correctly: upsert semantics, required value for open constants, and the secret-constant restriction. It is silent on error behavior and on what the response contains, which is a minor gap given no output schema exists.

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 100% and the parameter descriptions are already detailed (including the secret/value interaction), so the baseline is 3. The description reinforces open-vs-secret semantics and the {{const.имя}} template, but adds little meaning the schema does not already state.

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 pair and resource: 'Заводит или правит константу бота по имени', and adds what a constant is (a value shared across all bot scenarios, referenced as {{const.имя}}). This makes the upsert-by-name nature unmistakable. It does not explicitly name siblings like bot_constants_list or bot_constant_delete, so it falls short of full sibling differentiation.

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 a real usage constraint: an open constant requires a value, and a secret constant can be created but its value can only be set by the owner in the dashboard. That tells the agent when a call will be ineffective. It does not, however, say when to prefer this over checking existing constants with bot_constants_list first.

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